The whole idea is garbage because scenarios as they stand right now CANNOT contain challenging content.... and I am not even talking about a somewhat legit challenge ala Cata heroics (god forbid I mention BC heroics to the casual crowd).
"Why can't scenarios be heroic and represent a challenge worthy of dropping LFR quality loot?"
This has a very simple answer:
Any content that is intended to be cleared by three dps is not, and cannot be challenging in any sense of the game thus far... simple as that. Heroic Loot Pinata is what the crowd wants, and that is exactly what Blizz are giving them behind this meaningless "Heroic" brand obviously intended to make the crowd feel like they've accomplished something.
If the issue here is that the majority want a quicker model of obtaining loot... why not ask for heroic dungeons with no trash and only a couple bosses then. If they did something like this the time commitment to get your valor and gear would be very short, but everyone would still be exposed to the myriad of boss mechanics that form the basis of WoW PVE gameplay at endgame as well as being granted good opportunity to hone their skills, which I believe would better serve to encourage team-play and self-improvement than semi-afking through a right click snooze fest.