The rationale behind the upper limit of 22 knots was arrived at on the basis that, in the opimion of the Council, unirig sailors would be in non-racing survival mode around that point with two handed boats only just about able to race.
ergo; anything higher and noone is racing anymore - they're just trying to get round!
As said above, it's a draft, it's open for discussion prior to alteration or otherwise and adoption.