What I should of said is:

If you have 200 int and 150 charisma on your enchanter. I dont
believe it is a good investment to lower your int to gain more
charisma since at this point and having done some tests it seems to
me that it all pretty much works the same after 150 charisma.
However, if you can improve it without sacrificing INT by all means
do so. In the end, I suppose it is all a moot point if you can get
to 200 int, 200 cha.