If destro decides to use m4 on both tanks twice per minute they will simply be outpressured in the other 40s, just by order tanks being able to moral snare/root, armordebuff or dmg. (kobs m3 op!, sm m2 makes him unkickable)
(One trick pony ChCh and demolishing strike works too)
Dok m2 might help to relief some pressure but order can do fine with m1 or m2 on rp too.

Also dont forget that chosen and bo lose a tactic for that and have to wear snb -> less dmg-> less pressure 67% of the time.
Also keep in mind that without ChCh disengaging is easy for the order dps.
Basically the whole moral situation cant be compared on paper, the influencing factors, like order having more crit, more heal (rp/kobs) and better synergies, are too complex.
Of course I get that the whole thing is easier to pull off for destro since it is basically running by itself yet I dont see why a potential l2p issue should influence realm balance.

You know who I am.