Can an archmage select Spell Power more than once?

[Jdvn1]

Does that mean a rogue can take crippling strike four times?

Why would you?

Crippling Strike (Ex)

A rogue with this ability can sneak attack opponents with such precision that her blows weaken and hamper them. An opponent damaged by one of her sneak attacks also takes 2 points of Strength damage. Ability points lost to damage return on their own at the rate of 1 point per day for each damaged ability.

Take it the 1st time: You have the ability to deal 2 points of Str damage with a sneak attack.
Take it the 2nd time: You still have the ability to deal 2 points of Str damage with a sneak attack.
(etc)

Even if you could choose it more than once, it wouldn't actually do anything.