on steep climbs, this "hands on flat part of top bars" like in photos above is how I naturally climb. Part of it is that I find it helps having the "pull" on the bars as I force, it helps "brace" my legs pushing if that makes any sense, moreso than if I am in the hoods where I definately feel the lack of bracing compared to this. Dunno if the "opening of the ches" plays a part, but I do know its my natural go to position for hard climbing. (and of course another option of hand position that I use on and off riding regularly as well for a changeup)