I'm starting to think Pop just can't figure out how to get the best out of Walker. It's frustrating how often Lonnie gets subbed out when he's playing well just to maintain the rotation chart. A Spurs team trying to win games needs to take full advantage of Walker when he goes nuclear. A Spurs team looking to the future needs to focus on developing him if they're going to play him at all rather than subbing him out, because getting Lonnie in that mode more consistently would be allowing him to take multiple steps forward.
It doesn't help that Walker can easily be phased out if he plays with guys like Murray, Vassell and Johnson. For as much hay as was made about Lonnie being scared or whatever, the Spurs have a few guys who struggle to balance out calling their own numbers versus passing. That gets exacerbated when talking about situational awareness. If Walker is having a hot-shooting night, getting him the ball is probably more productive than running into the teeth of the defense or jacking up a long-two. I don't think the Spurs lack players who want to be the guy in crunch time. I think they lack players who are able to be that guy. Walker's the only guy with the clear talent to get his own good shot whenever he wants, but he has the mentality of a supporting player. Maybe there's no way to change that, but if there is, it's not going to be cutting him off when he's actually looking for his own shot consistently and then sliding him back in quietly when he cold and expecting guys who are used to being the top options are trying to take over.
I'd much rather Lonnie play 12-15 minutes (if not more) straight minutes and not come back in the half than try to stagger him. If he's too tired to come back in, that's what guys like Richardson and Primo are for. My guess, though, is that a guy in the shape Lonnie is in can probably play minutes into the high 30s rather than the mid 20s and would be able to handle that kind of load on nights when he's mentally locked in.