I know it's generally believed that the impact of individual practice minutes starts to go down once you get past the 25 (or so) minutes/day mark for any specific category. 

Is the same true for team (offense/defense) practice, or can you put higher numbers into offense/defense without the impact of each extra minute diminishing?

I think it is the same thing, but I have no official reason for thinking that.

Everything I have seen in the forums indicates that there are diminishing returns on team practice.  I think the consensus is they kick in around 20, but there is at least one respected coach who thinks they kick in much lower.

I'd say you see a ever so slight dimished return when you get over 10 minutes of OFF/DEF. 

for example the first 10 minutes may return a full 100% of the practice effort
the next 5 minutes (11th-15th), may show improvement of 90-95% of the original practice time
maybe the next 5 minutes (16th-20th), may only show an improvement rate of 75-90% of those original 10 minutes

throwing out some rough numbers

34 practices      practice    %Ret   outcome addit min                           cumulative results                      
minutes  10  =   +340       100% = 340 gain /  0 lost               340 practiced,  340 gain,  100% eff.
minutes  15 =    +170         90% = 150 gain / 20 lost              510 practiced,  490 gain,    96% eff
minutes  20 =    +170         80% = 135 gain / 35 lost              680 practiced,  625 gain,    92%
minutes  25 =    +170         70% = 120 gain / 50 lost              850 practiced,  745 gain,    88%
minutes  30 =    +170         50% =  85 gain / 85 lost              1020 practiced,  830 gain.   81% 

Nice post, Iguana.

Thanks for the responses - very helpful. 

Iguana, to clarify, are the numbers you listed hypothetical, or are they (at least roughly) based on actual data?

Ig- difference between 20 and 25 minutes 4%, so over 4 seasons a pair of identical players would reflect 4-6 fewer games of practice time, or arrive at the ulitmate destination 4 games quicker or slower.

problem with verifying that, is many have thought WE and HS GPA also contribute to how quickly one learns.

Overall, I have not noticed any difference between 20 minutes and 25 minutes rate of improvement.  My test is at 25 minutes, my guys get to an IQ after 3 seasons, that my guys get to after 4 seasons with 20, more or less, that is a huge advantage.

Only reason I bring this up, is your chart could be read by some rookie coaches as an invitation to only use 10 minutes of practice time, I would highly discourage that.

For the newer coaches, I would guess 95% of the vet coaches use 20 minutes or more of practice time for off and another 20 plus for def. - i.e. 20 to 25 minutes each more or less

other coaches out there, does that sound about right????

There is definitely a difference between 20, 25 and 30 min of practice.  I don't have quantitative data other than I have two teams where for a number of seasons I set one at 25 min for D and the other for 30 min D.  Prior to that I was a 20 min guy.  I noticed faster improvement immediately.  I was getting nearly every player to A+ their senior season in my 30 min team, but my 25 min team would only have 1 out of 5 or so make it to A+, probably because he had a headstart with higher IQ to begin with.  I have since scaled back my 30 min team due to diminishing returns and the indications that there would be less emphasis on IQ.  I will also say this, my 30 min team started at 30 min b/c I was transitioning from man to man to full court press and wanted rapid improvement in IQ.  My initial group of freshmen were all A+ by the beginning of or early into their senior season and made it to the championship game before losing.  They were mainly 2 and 3 star guys with one 4 star guy.  I figured most of them would max out in the personal ratings during their junior year, so I might as well slow that down a bit but increase the IQ.

these numbers are in the ballpark but they are by no means anything more than observances over the years.  It's possible the falloff rather than 100-90-80-70-50  is more of a 100-95-85-65-40 with a steeper curve at the end.

Generally after about 10 games of a players freshman season you should be able to predict, within a couple games, of when that player will reach an A IQ grade.

OR, in the example above the difference between 20 & 25 practice minutes is net gain of 120 minutes per season (625 vs 745), or 480 minutes over 4 seasons.  Which is about 3/4 of a season.
The 4% disparity in efficiency is a bit misleading as there also is an extra 680 (career) raw minutes put in with 25 vs. 20.

I used to strictly use 20 and no more before potential.  Now I use 30 in both off and def.  then take away at midterms for sh then add after grades are posted.  I like high iq and this is the only way I have been able to reach a+ when they are seniors.  And all my titles are after potential.

I increased team practice minutes after the potential era began.  Since the players were maxing out individually, I had to put the minutes somewhere.  Since then I have noticed the biggest advantage is to the freshman.  You can get them from F to C really quick at +25 team minutes.  After that the rate of improvement does slow down.

You beat me to it brip!

I think post potential I felt I needed to put the minutes somewhere and when a guy maxes you can run 0 in that area so occasionally a sr will have nothing to gain otherwise you max them to early and then they are maxed but you cant improve q's individually

Posted by hawkfan1992 on 10/28/2010 7:09:00 PM (view original):
There is definitely a difference between 20, 25 and 30 min of practice.  I don't have quantitative data other than I have two teams where for a number of seasons I set one at 25 min for D and the other for 30 min D.  Prior to that I was a 20 min guy.  I noticed faster improvement immediately.  I was getting nearly every player to A+ their senior season in my 30 min team, but my 25 min team would only have 1 out of 5 or so make it to A+, probably because he had a headstart with higher IQ to begin with.  I have since scaled back my 30 min team due to diminishing returns and the indications that there would be less emphasis on IQ.  I will also say this, my 30 min team started at 30 min b/c I was transitioning from man to man to full court press and wanted rapid improvement in IQ.  My initial group of freshmen were all A+ by the beginning of or early into their senior season and made it to the championship game before losing.  They were mainly 2 and 3 star guys with one 4 star guy.  I figured most of them would max out in the personal ratings during their junior year, so I might as well slow that down a bit but increase the IQ.

for sure hawk, IG is talking about a drop off in the rate, that the rate is non linear, but for sure, 25 goes faster than 20, and 30 faster than 25, the suggestion is the rate of increase slows as practice time increases, same as ind skills, except ind skills have a cap, not sure team stuff does????

Posted by Iguana1 on 10/28/2010 7:27:00 PM (view original):
these numbers are in the ballpark but they are by no means anything more than observances over the years.  It's possible the falloff rather than 100-90-80-70-50  is more of a 100-95-85-65-40 with a steeper curve at the end.

Generally after about 10 games of a players freshman season you should be able to predict, within a couple games, of when that player will reach an A IQ grade.

OR, in the example above the difference between 20 & 25 practice minutes is net gain of 120 minutes per season (625 vs 745), or 480 minutes over 4 seasons.  Which is about 3/4 of a season.
The 4% disparity in efficiency is a bit misleading as there also is an extra 680 (career) raw minutes put in with 25 vs. 20.

IG have you or anyone figured out where the end is?  My guess is it is pretty high, I have used 40 minutes at times for very short bursts, best I can tell, the curve is more linear than not.

matter of fact, if you told me it was 100% linear, I might believe you????

At this point anectdotal evidence seems to indicate that a team with IQs of B or better seems to be fairly competitive with a more experienced team.  We've all heard the rumblings recently that IQs don't matter at all...  I don't believe this for a second, but I do think that with the decrease in the rate of growth and seeming hike to potentials that happened with the last update that there is a strong argument for going 20/20.  I was doing 25/25 before the update but none of my players were maxing out (Knight; we've finished 4 or 5 seasons under the new engine).  I dropped it to 20/20 and I'm still not sure they're going to max out, have some juniors and seniors that are still growing pretty significantly. Wouldn't go lower than 20/20 even if they don't max out.  I want my players not to be total morons...