Well, I certainly wouldn't refrain from watering while in bloom - especially for the ones that bloom for a long time (I have a phal that has had blooms since October!) that would be quite a death sentence. I water as usual when blooming.
I am the type that fertilizes when I please, so I may not be the most scientific person to compare to, but I also don't go entirely fertilizer-free while blooming. Though I do cut back a bit - not as often and less strong. I try to focus fertilizing on active growth periods and most of mine aren't growing as actively anyway while flowering.
Just my 2 cents. Though I am sure there are others with more experience here!