I meant grip thickness is not that important, I also corrected this misunderstanding earlier. The hammer thing.
The grip thickness is very important, the wrong grip size will hinder you.
The hammer analogy, like everything you've so far posted in your 3 days here, is absolute nonsense. It's for battering a nail in from a distance of about 6 inches. I've no doubt 'techno geeks' could find an optimum hammer grip size that may let you hammer a nail in with slightly less effort, but why would they?
There's no techno geekery involved in grip sizes, it's just that now we realise that different sizes affect performance, there's no upcharge for having you clubs fitted with the right size of grip, and there's no upcharge for any different size of replacement grip, so what exactly are the geeks conning us about now?
Are they too expensive? Yes, there you have a point, but saying there is no need for a mid-size grip with 4 layers of tape when you have hands like Peter Scmeichel is utter tosh.