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I don't think you can even draw conclusions about the effectiveness of a bike setup based on a rider's race results. IMO results are much more dependent on the rider themselves. I love Reece and he seems like a fantastic dude, but I haven't ever really regarded him as a top tier racer. I bet if you forced Jackson Goldstone onto a Gamux with a similar setup and gave him a month or two to adapt to it, he would still be winning races.

Not necessarily—think of how people wrap their knees around the bike when doing a euro table. You can use a similar grip when hitting back to back corners.

Interesting about the gripping with the knees thing - having beaten the concept of “bike body separation” into my mind for the last decade, this goes against pretty much everything I’ve been working towards. Caveat: I’ve never ridden moto in my life, nor really watched a real moto race while focusing on rider position. On a mtb gripping with your knees, how do you get sideknobs to engage effectively while cornering given you can’t rly counterweight to not tip over in this scenario? Since knee grip would lock you into the vertical plane of the bike when it’s tipped?

Combine that setup with the ever-growing front wheel trend and we're slowly but surely getting there

Moving the BB forward in geometry terms is just lengthening the chainstay and shortening the reach. This does not require any eccentric BB options. Mechanically there might be reasons for tube butts you might want but the geo can be independent of this. Within the range of adjustment possible you are better off with an axle flip chip and a reach adjust headset to play around with Front/Rear centre proportion (which is what sliding the BB forward or aft would do). From an opinionated perspective I probably would not even bother with a reach adjust headset. People spend a lot...

Most DH bikes I’ve tested are 110-120mm head tube length. If you can fit a straight tube 56mm head tube, you have tons of room for reach and angle adjust headsets.

That sounds sick! If you can get the stack dimension close to where you want it, going slightly shorter on the headtube can be pretty helpful for a dual crown fork by allowing a wider range of adjustment. My size R3 (XL) Trek Session has a 117mm headtube length, the same 9mm upper / 1mm of lower headset stack, and 634mm on the geometry chart which is shared acoss all sizes. While the stock configuration felt super low to me, that could be somewhere around what you're looking for. I played with bar height a lot to get things dialed...

Came here to say the same thing about 130mm+ being a great number to see when looking at a size XL geo chart. Also seems to eliminate a bit of flex from the steertube with less spacers under the stem.

As a tall person, the one headtube standard is for them to be too short. I've never needed less than a 135mm headtube, and even with that I'm often running a healthy dose of spacers under my stem. And if I haven't convinced you yet, taller headtubes tend to be safer because there's more distance between the top and bottom welds on the headtube, meaning less leverage acting on them. You're more likely to see a short headtube ripped off.

Maybe take a look at what PMW makes? They're a pretty popular supplier... https://www.paragonmachineworks.com/headtubes/steel.html

There is no standard but for trail/enduro bikes head tubes in the 100-130mm range in 10mm to increments are the most common. For metal bikes head tubes under 100mm can start to be harder to pass testing with. It's typical to increase ~10mm/size so something like 100/110/120/130mm for a S/M/L/Xl is a starting point. If you are building a standard large frame for yourself I probably wouldn't go under 110mm. You can correct with bars and stems spacers a bit but it's nice to not have too much under there.