Just a reminder.... the NHL is not a development league. There is a high bar to entry. If Ed has not reached that bar, it doesn't make sense to throw him in so that he can "learn." You learn once you are already 90% of an NHL player and require mostly just finishing touches. If you are at 75%, you are not ready and you need more time in the AHL to get to 90%. And, this will probably come as a shock to some... talent has only a small impact on that %.
Now, if one wants to argue that Ed has reached that bar, that he is 90% of an NHL player, and that he's ready for just those finishing touches, be my guest. I think he's in a gray area, and it can be argued either way. I agree with some others here that he made too many critical errors in his NHL time and that he indeed could benefit from more AHL time. Has the past month benefited him to the point that he should be brought back up? That, I don't claim to know.