No.. not with straps. I use thumbless on back also. I actually feel i have a better grip like that. Basically your hand forms a hook and you pull with all your finger. Why not use the force of the thumb to pull down on the bar rather that holding on for dear life like in normal grip. And BTW unless you use very big weights dont use straps because you need to form your forearm. I never work out forearms separatley and they are pretty well developed, alot of people told me that. Maybe its genetics also, but i never used straps since i begun bodybuilding.

As stated, everyone is different so habits vary. Afterall, the important thing is to make that muscle grow