My traps get tired before my grip does. I got a kung fu grip!!
that said, I will use straps in the event that grip becomes an issue and is holding me back. For instance, one particular pulldown bar I use at my gym is slick and the gnarling has become smooth. I will work up to my heaviest working set without them, but use them on the heaviest sets. I then take them off if sticking to reps of 10 or higher.
I can do shrugs without them easily, but, it's ironic that my traps aren't impressive. Even when I did use straps, my traps were still not impressive. I do armpit rows/monkey rows with 85lbs DBs and shrugs with 95-100s, no straps, and my grip is great, and my traps will burn after the set. Still, nothing. I am at a loss.
I have Popeye forearms though and I am told it's one of the first things people notice about me.