Yep, thats what I say too. SP is about rate and condition. (And similarly I saw a variability in gains from high to low of around 60% I think it was.)
On the wider note of 'involvement', a player doesn't get high ratings and consume more condition if he is more involved. A player who is more involved will consume more condition - if that involvement is doing good things he'll get higher ratings but he can also be heavily involved doing bad things and get a low rating. So be aware of the type of involvemt - some players put a lot of effort into being bad (and still make good gains). (Also some players can do the eye catching things, get good ratings but use less condition.)