Like Shaver, I maxed out wisdom beacuse I wanted to maximise my level - but I agree mathematically it doesn't seem worth it.

To make back the skill points you spend on Widsom, you need enough wisdom to gain an extra level for each point spent. With each point only worth 2% XP, you need to achieve 50 levels AFTER spending the point to get that point back. I have never heard of anyone making it over level 50 in total across the game.

Of course extra levels also give you ability points, but there are generally skill points that give you much better bonuses than ability points. For example, destruction increases damage much faster than intelligence, regeneration is better than strength, mana efficiency is better than willpower etc.

I started by keeping Wisdom as high as possible until I got to 5/5, then I gave up as the bonuses weren't up-to-scratch and I was really short on skill points at that stage of the game. It wasn't until I was up to FoV that Wisdon became attractive again - by that point I had maxed out most of the useful skills (so ability points were the only way to improve my effectiveness) and had skill points to burn.

Anyway, have a great Christmas!