Every team I've talked to starts out with some X-factor they think they need to assess for. It's my belief that if you can have the discipline to stop filtering for X-factors, you'll build better, more effective teams, because those factors are really just vectors for personal biases.
Regardless of whether you agree with me about that, I think we can all stipulate that if work-sample technical evaluations work (and: they do), most of what companies try to evaluate in on-site interviews is stupid. No part of working effectively with a team requires timed recall of how to implement a stable quicksort, or reversing a doubly linked list at a whiteboard.
At the very least, using work sample tests allows you to build an on-site interview process that honestly engages with "team fit" (or whatever your X-factor is).
My guess, though, is that when more teams adopt work samples and then go through the motions of trying to design a pure team-fit interview, they're going to realize --- once they don't have "implement Bellman-Ford on this whiteboard" to fall back on --- how unequipped they always were to evaluate team-fit in the first place.