I didn't see much more than a game and a half, but did I miss the part where Edvinsson was really sound defensively? He was flashy and full of talent but I can't count the number of times where there was a 2-on-1 created because he misread the play and jumped when he should have settled back.
The reason Seider made the jump to the show right away was because his fundamentals were so sound. He rarely got beat defensively and was always in position. Now Edvinsson may actually have more ~skill~ than Seider but if I were a betting man, he is going to spend time in GR until he is over ripened.
I just don't see anything Ed can learn in the AHL that he wouldn't learn better and quicker at the NHL. Becoming a steady Eddie in the AHL is pointless when you want this guy to be a dynamic game-changer at the NHL level. He needs to learn the timing of when and how to jump and when to retreat at NHL speed not AHL speed.
To expand, to your point the misreads and all that is stuff that Ed had already figured out in the SHL. These are all things he knows how to do, gap control, pinch/don't pinch, etc... "Learning" them in the AHL just to have to "learn" them again at the NHL speed is pointless. What he has to do is take what he already knows how to do and apply it to the NHL speed.
There will be mistakes as he calibrates to NHL speed. That's just the type of defenseman he is. Once he's calibrated tho... that's when the fun starts.