I think I read somewhere that a fastbreak offense falls back to motion offense if forced into a halfcourt set. I'm wondering what are the functional similarities/differences in the sim between running a dedicated fastbreak offense and running the motion at uptempo. Are there noticeable differences in terms of shots taken, fatigue, required skills, etc?

if you are just starting, I would recommend against fastbreak because the biggest difference is that there is no slow setting in fastbreak - now and then slow is the way to go

I cant comment usefully on detailed distinctions between FB and MO in the engine

its probably fair to say that in the half-court, fastbreak is motion-like. i wouldn't go any further, they are materially different.

fastbreak is significantly different than the other 3 offenses. one of the main things is that you can build your scorers differently, your back court scorers can score competently at substantially lower lp/per levels than the other offenses, if they have good spd, bh, and ath. same for front court players, but with a much greater focus on ath than the others. the net result is when you are focusing on defensive skills for players, those guys often end up being solid scorers with crap lp/per, which means you need to prioritize offense in fewer players. high end 3pt scoring still turns pretty heavily on the per rating, but you can put together a decent 3pt offense with lower levels of per than other offenses (this is meaningfully true with motion compared to triangle/flex already, motion spins off of bh for 3pt scoring more than those two, and fastbreak is another step in that direction more or less). you still want a couple studs to lead your offense, if you can swing it, and you definitely want to lean on them hard if you can get them - fastbreak is quite flexible in terms of where your scoring comes from, definitely feels more flexible to me than motion in this regard.

fastbreak is also higher pace and higher fatigue. you'll have more possessions in a game, but you'll get more tired as a result. the extra fastbreak fatigue is about half of the extra fatigue from press. you also will pay about 1-1.5 extra turnovers per game, for running fastbreak. this is mostly a floor, you cannot achieve parity with other sets in terms of turnovers at any level of bh/pass (if you have much better bh/pass, you'll have fewer turnovers than your opponent, but this is an advantage that is fairly constant at any level of bh/pass, when compared to the 3 'main offenses'). you can however make this number higher if fatigue starts to become an issue (with fb without press, 1 turnover a game is a good ballpark, with fb/pr, 1.5, but its with fb/pr particularly where you risk higher fatigue leading to a much higher number of turnovers - although of course the press also allows you to force many).

running uptempo versus normal, the effects of uptempo with a fb or motion offense, there is really no difference there. i mean, uptempo does its thing or whatever, but its not like the fundamental characteristics or differences in the offenses, really change based on whether the its uptempo or slowdown or what (except that fb can't run slowdown obviously).

for what its worth, the way i think about fastbreak and uptempo motion in the spirit of your question is, neither of them really give you the run and gun offenses we see in the NCAA. fastbreak more than motion, but don't expect to see it in the fastbreak points on the box score. the reasons to play fastbreak are generally for the higher pace and/or fatigue (which often makes most sense paired with press), and for the offensive flexibility, which i do think sort of simulates a run and gun offense by allowing you to score with ath/spd/def instead of lp/per (but you won't see the easy buckets in the box score or play by play, so it will never really look or feel like a college level run and gun offense). fastbreak does behave materially differently in both those regards, so you can build different systems, different schemes, around a fastbreak than around the 3 main offenses.

on the other hand, uptempo motion isn't really a system. there's nothing to distinguish it from regular motion, more or less. you can't really build around it. uptempo motion is really a tool for m2m and zone teams who want to run uptempo simply to increase the pace, to add more possessions, either to try to tire out their opponent (who presumably is pressing in most such scenarios), or to try to give them more time for reversion to mean against an inferior opponent. or maybe to get some backup line action against the opposing backup line, or whatever.

Ah, super informative...I asked the original question because I was wondering if one could approximate the fastbreak offense by running motion uptempo (while still maintaining the flexibility to run motion slowdown). It sounds like these are fundamentally different sets in terms of gameplay, which of course makes sense. Lots of food for thought, thanks!