Details,
I do it both ways. Last year (and the year before) I rested my catcher (Dur. 87) every 10th game, then my CF (Dur. 87) the game after that, then 2B (86), then a COF (81), then SS (83).
In the last 35 games or so, last year, my 2B, RF and SS each hit 99% 3-6 times....and then I rested them again, sometimes a couple of games for one COF.
Catcher started 144 games. (I think I can get 6-7 more as I sub him out in late game winning situations. He's started as many at 149. Led the league in hitting). CF started 149. 2B =144. COF=135. SS=144.
CF got 1188 innings (sometimes being subbed out for defensive purposes late game) 2B got 1291 innings in fewer starts. He didn't get subbed out late game (I won 98 games, so late game defensive subs occured fairly frequently). COF got 1189. SS got 1301.
Innings, of course, are the real key.....but the difference in games at 100% is significant between 81 and 83 Durability. 83=144 games as SS. 81=135 as COF. 1301 innings to 1189.
By subbing every tenth game, I postpone the 99% issue until the last quarter of the season for all but the C and CF, who never hit 99%. Catcher accrue 1159 innings with that 87 Durability and no 99% issues. He's had 1198 innings twice.
I also had a guy that played at 1B against RHP and RF against lefties. He had a Durability of 84. I started him every game for more than 100 games. Then I sat him at 99%. He started 147 games (including 6 at DH during Interleague), so I had to sit him 15 times. I thought I would get more from him, considering he was playing 1B 50% of the time (80 starts). But it really didn't make much difference. My SS got about as many starts playing a more demanding position, with a Durability one point less.
Hope it helps.
moe