SVonhof I had all my irons grouped into same-length groups, about 12 years ago and had plenty of fun with them: still have the two sets I had made.
1,2,3 irons same length as the 2-i
4 & 5 same length as the 4=i
6,7,8 the same length as the 7-i
9, P/W, S/W, L/W same length as 9-i
My theory was quite simple: if you can have the same swing for the same clubs in the group, the loft and head weight will provide the distance differential, which should result in consistency ball-striking. Bryson DeChambeau's results have proven this theory to have substance.
The difference is DeChambeau probably has the same head-weight for all his irons, and is not constrained by the 7-gramme weight separation I had to work with using my normal SMT MC heads and Cleveland TA4's. I suspect DeChambeau is using a head weighing the same for all irons - I'd guess probably 270-274 grammes which makes it more consistent that my original experiment where I was stuck with the 7-gramme weight separation between heads.
The lofts on the irons shown in the link you posted are massively jacked up. A 5-i with 23-deg loft? that's even stronger than a standard 4-iron at 24-deg!!
Imo, Single-length irons will become more popular as hybrids, rescue and fairway woods take over the long-iron domain for a lot of amateurs.