Hey, how about another pure conjecture post, aye? Let's say Carl Crawford loses all of his speed, okay, not all, but he goes from being one of the fastest men in the game to slightly above average, what type of player would he become? The skill sets of taking walks and hitting homeruns while doing little else is commonly mislabeled as a Moneyball player, but there's also a term thrown around about these type of players, "old player skills". The theory is players walk and hit homers more towards the middle and end of their careers as such things as speed deteriorate.
Of Crawford's 1,469 total bases roughly 53% have came via doubles, triples, or stolen bases and 22% of his total hits are doubles or triples. Compared to a power hitter, Jonny Gomes let's say, who had 31% of his total bases invested in "speed" plays and 24% of his hits. The difference of course is the emphasized category of hit - Crawford had as many triples this season as Gomes has in his career.
We often talk about Batting Average on Balls in Play and Line Drive percentage, using the latter as a predictor of the former. Carl's speed obviously affects the defensive efficiency when it comes to dealing with him; take a look below at his "luck" and infield hit percentage to get an idea of how prone Carl is to getting a hit that doesn't even creep beyond the infield dirt.
Remember Carl also hit two inside the park homeruns, let's presume that he's stretched some singles into doubles as well, essentially we're taking the added bases away.
Total bases: 1,469
Subtracting projected added bases: 1,269
Delta: 200 bases/50 "runs"
So assuming that Carl's BABIP would regress towards the mean without his legs by taking away an estimated amount of bases we'd transform his line into something like this: .253/.292/.380. Now that line is quite unfair to Carl since we're assuming he'd maintain the same hit tendencies without his most vital weapon, so to give some credit ot the theory of a baseball player evolution let's assume a few of Carl's triples and doubles become homeruns, a few of his singles doubles, ect. while maintaining that his speed is still average to slightly above.
If Carl were to add 90 bases through a combination of doubles and homeruns his slugging would move to .405, and assuming that his eye would improve in inverse to the pitcher's aggressiveness lifting his batting average, but more importantly his OBP into at least the .320 range you have a .725 OPS producing left fielder, placing him below league average last season for all sevens.
Obviously this is far from an exact science, but if nothing else I hope we've opened up the thought process on just how much of Carl's game is speed based.