Arelith

Took the feat, Didn't increase rank.
this on a lvl 6 wizard.

On that note, Wiki lacks any information on the feat, And the unification on skill feats related to hide/ms. (unless I'm blind, Wich is always an option with me) prob a lot more lacks on the wiki tbh.

The levels are gated at 12 and 21. A level six wizard will automatically be level 1 thanks to scribe scroll. The feat should kick in at level 12 and you will see an increase. A pure wizard also gets a second and third tier at level 12 and 24 levels respectively.

So scribe scroll + Imp Dwoemer + 12 wizard levels gets your tier 3 that kicks in at level 21.

However, may want to consider asking for a XP drop on a wizard build. Imp Dweomer is usually a waste because wizards:
1.) Get 1 automaticall for scribe scroll
2.) Get 1 for 12 levels
3.) Usually want to take Wand or Potion which grants 1