This only means that you can no longer ignore one scale while reaping the rewards of another.
I don't feel this is particularly weakening, but I've never been a fan for making some ugly monstrosity of a pretender with 90% of my points into him.
Even taking a 9 Path pretender sometimes makes me cring and wonder where I'm scraping the points up from. So that's more of a personal bias and I don't fault Keir's thinking for it.
IMHO it makes for just as many options, just not as 'complete' in the mindset of some of the players (If I'm doing a blessing, I might as well go hog wild!)