About high B, I think back to when I was just starting out playing the Irish flute, in the 1970s, and I read a quote by Cathal McConnel talking about somehow making those high notes shorter to smooth out your playing. I can't remember how he worded it.

It didn't make sense to me at the time, but years later, when I got pretty good on the flute, I was playing some reel and a guy asked me what I was doing to make all those high B's so sweet, so they didn't jump out. Turned out I was doing what McConnel was talking about. It wasn't a conscious thing but something that slowly had become part of the way I play.

When I was trying out loads of Low D whistles it became apparent that B in the 2nd octave and E in the low octave constituted the benchmark notes to discover where each maker drew that devilish line between high note sweetness and low note power.

Be sure you leave the other fingers off, playing high B xoo ooo on Low Whistles, or B might not speak well.

About the fingerings I posted, as far as I can tell they've been around a long time, probably longer than some of the whistle fingerings I see nowadays which appear to be based on recorder and Boehm flute fingering systems.

There's a whole set of clarinet fingerings that have the purpose of going over the break easier, and as pointed out various woodwinds have trill fingerings. All these things make what would be complex note-changes much easier, allowing faster and cleaner playing.

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Richard Cook
1978 Quinn uilleann pipes
1945 Starck Highland pipes
Goldie Low D whistle

I've been looking for a chart that includes fingerings like the ones you posted earlier. There are comprehensive charts available for alternate recorder fingerings, but I haven't found anything comparable for whistle. The closest I've come up with is this one: https://i.pinimg.com/originals/02/9b/cd/029bcd9f61dba9a3391e41b2e8103466.jpg