I think VDN isn't far off with Tyrus. When you get "good" Tyrus he's the second best big on the team (if you get the rare glimpse of "playing at his potential" Tyrus he is the best big on the team). But most nights you get "content to shoot jump shots and not run" Tyrus, so you're better off sitting him after you see he doesn't have it. Only problem is that I think VDN saw bad Tyrus for such a long stretch he's just sitting him anyway, even on nights when he looks good. If he can get back to letting Tyrus play when he shows up to play, I think we'll be doing the right thing.
Now maybe it's a case of a bad feedback loop, where the coaches get frustrated with the player, so the player gets frustrated with the coaches, and it just gets worse and worse, I don't know. But other than a stint at the end of his rookie year where he looked like a future DPOTY, Tyrus has had basically the same issues with consistency and effort under Skiles, Boylan and VDN, so you've got to think Tyrus has brought most of it on himself.