It's not "necessary". I'd have to look at the specific question to explain why. When cutting, prov is going to help with creating a dry hard look, as well as freeing up test, as it binds to SHBG. For most people doing a cutting cycle with var and prov, I would combine these like this.
1-10
test 400-500mg
adex
4-10
prov 50mg ED
avavar 50mg ED