Yep, that’s one model of the effigear, which is incompatible with the standard pinion mount for the 7 gearboxes they make, plus the new effigear mimic.

So yes you can design a bike around that single model of gearbox that’s been out for at least 6 years. But that’s a niche of a niche, so not exactly mass market.

Jack Reading’s UCI WC results

https://www.rootsandrain.com/rider983/jack-reading/results/filters/seriesgroups244/

I seem to recall he snapped his chain on that 2017 Ft william run, so ignore that one.

His 2017 year doesn’t seem particularly better or worse than those either side.

Jack wouldn’t tell us the weight of the lead but just said he’s been working with Chris Porter from Mojo, and through testing has found that by placing the extra weight behind the stem and at the bottom bracket helps to calm down the forces and roughness from tracks, keeping the ride planted.

It is track specific, however, as Jack says the extra weight feels good on the fast and rough tracks but made the bike feel a little ‘dead’ on the tight and twisty sections.

The weight behind the stem has nothing to do with a gearbox bike putting weight around the BB. It’s hard to know what the effect of that was without seeing exactly where it was mounted and how much it was. The important conclusion is that the ballasted frame wasn’t universally beneficial, it just helped in one specific situation. What that means is that a lighter frame that can be ballasted for stability is more versatile. A heavily built frame will be worse overall because you cannot remove weight to tune it for different situations.

But that’s a niche of a niche, so not exactly mass market.

Pretty much sums up gearbox bikes.