IMS had ratings for each leg and length of the course... by all accounts it is accurate but a PIA to use for the RC .. ... It contributed with other factors to the demise of the IMS.

IRC is working hard to gain acceptance in the USA. The cost of the certificate and the PIA to the owner to get an individual cert has slowed it's acceptance( PHRF is a lot cheaper and you already have a rating certificate ... just pay your 35 per year dues and you are good to go another year). The IRC racing has been viewed as fair from what I can tell. (IRC is not a problem for the RC since a single number time on time calculation is available in all of the scoring programs used)

SCHRS and Texel are not used in the states.... We don't have a really good reason other then traditionally we have used Portsmouth.

In practical terms... we have a bunch of boats that are sailed in the states but they have not been measured for texel or schrs (hobie 20 Prindle 19MX) .... So we don't have a complete set of ratings which automatically stops wide spread use of a measurement rating system. US Sailing and the Multihull Council have not taken on implementing a measurement rating system.

US Sailing manages the Portsmouth system for all of the monohull dinghy's as well and so managing two systems (portsmoutha and measurement) would be a lot to ask.