Yeah, that's fine. Like previously said, they don't have to be exact. I do the same thing you're doing and I'm noticing good results, so it still works regardless.
It surely works, but no good in causing fluctuation in hormone.
Buy a Tajima knife with acute blade for fine cutting (you don't have to use the blade tip though). I use it to cut 1/8 pills precisely. Better than any pill splitter!