EDIT: You've edited your comment substantially since the time I posted this reply, so now it looks like I'm writing with disregard to your arguments, and I'm thus editing my reply too.

I certainly don't have an idealized view of the legal system in general, or criminal defense lawyers in particular -- on the contrary. If there really is a complete disconnect between the lawyers' incentives and the destiny of their clients, then I can imagine that they wouldn't notice correlations like these (though I'd still find it implausible, given the purported magnitude of the effect).

However, if such incentives do exist, then I find it absurdly implausible that lawyers would be unable to figure out these correlations and take advantage of them. (Even if they're theoretically unable to influence the scheduling, no bureaucratic system is immune to manipulation if there are smart and determined people with the right incentives.) As innumerate as they might be, there's no way lawyers could be so incompetent that a few social scientists could just show up and point out that they've been doing their job suboptimally because they're unable to put two and two together about such a simple issue.

On the whole, when you argue that the interests of lawyers and their clients are misaligned, I find that a plausible claim. But when you argue that they'd be unable to figure this out even if they had the incentive, that's a far more extreme and implausible assertion.