If they made a real effort to bridge the gap then they deserve more credit than I was giving them, and they're doing what I previously expected them to. So good on Bungie then. But ...
Retcon is still retcon even if you do damage control. Some of the "extra spaces" they created don't fit well, were IMO unnecessary and lead to a rather less dramatic start to Reach's destruction than previously understood to have happened.
The way they played it in the original intro reveal was much, much better ("You picked a hell of a day ..." etc).
I guess they needed to add some more turns to the drama ("We safe planet moustache man!" then "nooooooooo").
You don't say.
Does the limited edition explain how a helmet survives a planetary glassing? Was it in the bit they left?
I want Halo 4 to be about Arby looking for Chef (with Shipmaster as his grumpy sidekick).
The whole planet wasn't glassed as the covenant where digging for the forerunners artifacts.
I would advised you to read Fall of Reach and First Strike if you really want to know more. Actually add Ghost of Onyx if you are interested in the Spartan III program.