Completely sensible.From your response here and elsewhere it is evident that these changes are balance related and the flavor component is purely secondary. I'm not seeing much in the way of quantifiable evidence that a balance change is warranted or unwarranted by either side of the discussion. Most of the people in these ToD discussion threads are translating their experience as users (dark monks) and observers (party members) of the ability into an opinion on balance. Balance is a murky subject but I do believe a component of balance has to be the community's feeling as a whole. I do not want an ability of my character to invalidate or ruin the play experience of another group of players. Likewise, I would not want a balance change to completely invalidate a group of player builds even if it helps me compete in game with my class. In this case community perception of balance is inherently flawed because of a bug allowing quadruple and quintuple ToD effects. I suspect this bug also inflates the documented rate of double or triple effects (wind stance) versus expected single effects.
Even with the tools I would assume you as a developer have access to, I do not believe it makes sense to attempt a balance change on an ability that is bugged so heavily toward the over-powered side. I simply don't think a test server exposes the ability to enough experience to gauge balance. I think the most sensible change for Update 7 is to fix the clearly over-powering bug and give the community as a whole a chance to experience touch of death that is working according to Update 5 documentation. An end game balance change may be warranted but there are far to many people affected by this change not to give it due process.
As many dark monks have already mentioned, there is a balance issue but it has to do with scaling of damage per level not damage at end game. The issue with even a single ToD effect at level 9 is that it prevents other party members from contributing at all to many boss fights in that level of content. The quadruple and quintuple ToD effects extend the one-shot boss effect into higher level content than it would otherwise. If I were to make a balance change effective in Update 7 it would be to scale ToD based on character level so that only at level 20 did ToD effects hit for 500 while leaving leaving double and triple (wind stance) effects alone. By making it character level we spare our multi-class friends from undue harm.
Lastly, if an end game balance change must happen in Update 7 I'd rather see negative energy damage type and rather than a fort save a lowering of ToD effect of 500 to something seen as reasonable while retaining the double and triple effect chance so wind stance and two weapon feats are not impacted as much as a secondary effect of the balance change. This method would also put multi-class and single class ToD users in the same boat balance wise. I'll say again that personally I think making an end game balance change could only be accurately evaluated with a non-bugged version of ToD after Update 7.
There's no reason to triple nerf a skill because the initial implementation had a bug in it. Fix the bug. Leave it alone. Revisit it later after you've had the chance to observe the non-bugged version. This fix requires a scalpel, not a chainsaw.