I don't know how much it really means obviously, but it certainly can't hurt.
I can see why you view it as reason for optimism.
To be honest, I just really have a gut feeling (That and 5 bucks will get you a cup of coffee at Starbucks
)that Mankins ends up staying. When you figure that some of the other important players such as Brady and Wilfork have now been taken care of, the youth invasion that is contract-friendly right now, the problem solved with Seymour leaving, and the importance of Mankins to blend in with the whole 'physicality' aspect, I do not see it as anywhere beyond the realm of possibility.
Chances are, the labor uncertainty may have also played a role in the negotiations, as the team may have been leaning slightly more towards the conservative side--rather than taking too many risks. I think the negotiations will be in a better light once the uncertainty in settled. That, and the fact that Belichick has supposedly been attempting to reach a middle ground with him can't necessarily be a bad thing either.
I think the team comes up a bit in the end financially speaking, and Logan appreciates Belichick's having his back + the comraderie with his teammates enough to meet somewhere in the middle (assuming the numbers are pretty close at least).