Great question — answering as the UphillTech team:
I also hold over the shifters sometimes; it's quite effective. I have Ergon GP2 (smaller than the GP3s I mentioned in the linked question, which are now on my folding bike) grips on mine, which make the primary position slightly better but also provide a mini bar-end. In very tight vegetation that's not ideal, especially if you're going fast, but I've only snagged mine twice, and slowly, in thousands of km despite riding some very overgrown trails. Bar-ends started out as MTB accessories after all. Ergon do make a GP1 with no bar-end at all. The angle of the hand pad and that of the bar end can be set separately; the pad angle is quite important if they're to spread the pressure and not...
Full answer by Chris H: https://bicycles.stackexchange.com/a/100402 (CC BY-SA 4.0).
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