Their latest moveable feast is the rules surrounding the number of 'federation trained' players clubs in Super League can have on their books.
For anyone who missed it, this was meant to replace the old overseas quota, replacing the original passport criteria - which had become increasingly defunct because of the Kolpak ruling and the glut of EU travel documents being used by every man and his dog - by looking at where players began their professional careers.
If you started in Australia or New Zealand, or indeed in rugby union, then you would be classed as 'non federation' trained.
As a concept, it's a pretty good one, designed to force English clubs to develop their own talent.
But then the tinkering started.
Hull KR set the ball rolling by appealing for an exemption for the ageless Stanley Gene on the basis the old fella had been here since the great schism of 1895.
I exaggerate, of course, but you get the idea.
Then Fax's Shad Royston, as Australian as Neighbours and the Sydney Harbour Bridge, managed to wriggle through the net on the grounds that he first came to England - to play for Batley - before he was 21.
Apparently, that means the RFL decided he is a bona fide homegrown talent, setting a precedent that presumably extends to other young Antipodeans.
Now, without wishing to disparage the fine job Gary Thornton has done at Mount Pleasant, I cannot imagine what Shad learnt there that he hadn't already picked up during his formative years with NRL giants Cronulla Sharks.
That is no criticism of Royston, who is merely giving himself the best chance in his career, but it certainly broke the spirit if not the letter of the new law.
Then, late last week, came the carte blanche dispensation for all 14 Super League sides.
All overseas players currently contracted to Super League clubs will retain their existing status for as long as they remain with their current employers.
That, for example, means a club currently employing an Australian travelling on, for example, an EU passport, can retain that player on the same basis from 2009 onwards.
Only when Mr X leaves for pastures new will he become subject to the new rules.
Talk about a cop out.
I understand that is already causing problems in some quarters.
Apparently, one club allowed an overseas player they wanted to keep to entertain other offers because they could not fit him under the new quota.
That player - who allegedly wanted to remain with his current club - then signed for a rival team, only for the RFL's backtracking to leave both him and the team that let him go high and dry.
Elsewhere, Wakefield - who had prepared to lose the likes of Jason Demetriou and Adam Watene - and Castleford - who were ready for life without Andrew Henderson and Mark Leafa - now face some hasty salary cap calculations to see if they can manage to keep their players after all.
All this underlines just what a mess the current situation has become.
I have a simple request: the next time we make a rule, can we please stick to it?