After speaking to dozens of players, no one can actually provide any purpose to why decrypting an engram is necessary. (Legendary & Exotic)
The level of the engram is determined at the time it drops. So there's no reason to hold onto them. The roll is entirely random, so it is no different than what happens when you pick up a 'rare' engram, where you get the item immediately. So what purpose does it serve having to go to a vendor to 'open' an engram, when you could just give me the loot at the point of drop?
So with that in mind....
[b][u]Suggestion:[/u][/b] Remove the need to 'decrypt' engrams OR provide some kind of logical reason or need to do so.
Made into a poll, to allow an easy view of popular opinion.