I use a 33/394 grief zerk. I have 37ias from fanata and 20ias from highlords, my question is will I hit the last smite breakpoint with only 33ias on the zerk or do I still need 34+ias on zerk?
If you go to www.battle.net/diablo2exp and click on the files link and scroll down there is a link for a weapon speed calculator. Click on the link and it will take you to a weapon speed calculator that can tell you how much ias you will need to reach the breakpoints for smite.
Simply enter in all the info the calculator asks you and it will do the rest.
If you're using Smite, I'm going to say yes. This should help you a bit, if you’re using zeal or smite. If you're getting 37 ias from fant, and your grief only has 33, I'd treat it as though they both have 35, to make it nice round numbers for you to work with.