fingerboard Open grip: 1 knuckle versus 2

My fingerboards have several horizontal-edge holds which are deep enough to grasp with two different "styles" of Open grip -- either

1-knuckle : with the main bend of my finger at the joint closest to the tip (with the next-farther joint much straighter and aligned roughly vertically), or

2-knuckle : with the main bend of my finger at the joint second-closest to the top (with the closest joint much straighter and aligned roughly horizontally along the top surface of the fingerboard edge).

Seems obvious that the 2-knuckle style is stronger, and the priority of fingerboard training is to address gaps in strength capability, and to get really good at hanging with Open grip (instead of Crimping) on smaller edges.

Not.
(for me anyway)
My static hanging strength is roughly similar for both styles, in any context where I can systematically measure them. My 2-knuckle grip is at best only slightly stronger than my 1-knuckle Open grip.

Anybody else played with this?
Anybody have some insights or guesses about why I might be experiencing this?

What does it imply about my training? Is there a reason for me to do separate exercises for 2-knuckle Open in addition to 1-knuckle Open? Or a reason Not?

Thanks,

Ken

P.S. On small but not super-small edges, my Crimp grip strength is at most only slightly stronger than my 1-knuckle Open grip, but that's a different matter (or so I assume).

I've played around with it. When I'm doing a hard deadhang on a flat, small edge, I find it hard/impossible to use a true 4 finger open hand grip. Instead, the PIP joints (the middle knuckle) of my ring and middle fingers will flex and the DIP joints (the ones towards the finger tip) will slightly hyperextend. My pinky and pointer finger are the only ones in what I'd consider open position (DIP joint flexed, PIP joint straight).

If I want to use a totally open handed grip on a difficult flat edge I need to go with a 3-finger grip. My pinky is significantly shorter than my other fingers so maybe this has something to do with it.

I've found my 4 finger faux-open-grip and 1/2 crimp are pretty much the same on a deadhang. 3 finger open lags a bit behind. IMO, crimping often wins out in actual climbing movement because it's better for exerting outward force on an edge. When I was recovering from an A2 pulley strain and forced to use an open handed grip with my injured hand, I couldn't lock-off as deeply on that side and had to resort to using more momentum....which made latching the next hold harder on my healthy hand.

I'd be interested to hear from others about this too.

Thanks a lot for the detailed analysis.

Which makes me realize that my claim was a mistake.

With four-finger open grips, Yes surely I can grip much more strongly on a ledge deep enough for 2-knuckle than on a ledge which only allows 1-knuckle Open.

I think that's because the deeper ledge allows more fingers and joints to contribute more fully. So some fingers might be working the 2nd knuckle articulation and others might be working the 1st joint, and some might be working both - (and out on real rock with irregularities there tends to be more opportunity thru clever placement to engage more joints).
While with a smaller ledge it's difficult to effectively engage more than three out of four fingers in an Open grip.

Also I would guess that most people's hand structure is well-optimized with the four-finger grip to enable the different fingers to support each other against rotation + shifting.

My observation was about two-finger and single-finger Open grips, which (for reasons good or bad) I've been training mostly lately -- and therefore measuring.

I guess this shows that when you (unnaturally?) isolate specific joints, you get unexpected results -- which might not matter much in most outdoor rock situations.

Ken

my experience is fairly similar to charles. it is basically impossible for me to go 4 finger open due to the big difference in lengths of my fingers. even the 4 finger half crimp looks kind of funky. for open i go 3 fingers. on an equivalent hold, my 3 finger open is as strong or stronger than my 4 finger half crimp.