Well, I've managed to do something interesting

[Curmudgeon]

Namely, I've managed to get Knowledge Devotion banned. The archivist having it, rolling for it, but not actually using any of his ray attack spells this session may have contributed as well.

I think that's addressing the issue of a powerful (Tier 1) character indirectly rather than overtly. Sort of like throwing up 30 KPH speed limit signs in town when someone shows up with a Ferrari (ignoring the autobahn nearby). I've used Knowledge Devotion quite frequently, but mostly for Rogues. (I keep up with Tier 1-2 characters just fine.) I suspect the context is what matters here.