If you did catch him, Carriker was on Unsportsmanlike Conduct earlier giving his insights on the 3-4:
https://soundcloud.com/unsportsmanlike-conduct-1/jan-20-seg-12-adam-carriker-former-blackshirt
Says it's going to take a while to learn the new system... as in Years.
Says new system is total opposite of old system... could not be more different.
He also says that it immediately creates a much more unpredictable alignment for offenses to decipher. That is a big bonus in my opinion.
You are right that it sounds like an awful lot of education that is about to come our players way, but I trust that he is a solid teacher and we definitely have position coaches that will get buy in fairly quickly. He did also state that these are young guys and as opposed to NFL guys don't have a huge amount of muscle memory in the 4-3. They will be able to pick it up I think. Won't be perfect right away obviously, but I don't think it will be years till we see the benefits.