Dave, since the dawn of rating rules (look back to JOG, SORC, RORC etc) boats have been 'tweaked' to the rules. It will always be the case.
What has been highlighted, however, is a major flaw with both SCHRS and TEXEL. Therefore at the next annual review meeting, both of these bodies should be looking to address this failing (assuming they know about it).
I'm not familiar enough with PHRS to know whether they have a similar situation, but I suspect not as their handicap system is anecdotally based.