A Tommy replacement? He sure beats Donnie.
Tommy's not going to work forever, unfortunately. There's a long-time gig to be earned; if Scal does well, he could theoretically be settling himself into a job for the next twenty years.
And while I know Mike and Tommy are on road a ton and have to do a lot of work, it's got to be an easier life than slugging it out as an assistant coach. If Scal's only going to be going out on the road a couple times a year, maybe there's a lifestyle decision at work here; maybe he wants to be able to settle down. Assistant coach, unless your name is Dante Scarnecchia you don't really have ANY job security.