Like I said on UFA day, I don't think it's a good assumption that Adams would have been available later. I doubt Shero really wanted to give him two years, if that were the case he most likely wouldn't have even made it to 7/5. If Shero was willing to give him two years in the end, that tells me that another team was offering him at least an equivalent deal if not better. Shero's isn't perfect but we all know he's not a moron. He's not going to guarantee a 36 year old fourth liner two years if it wasn't necessary.
Of course, he could have just moved on from Adams and I know that would be preferable for a lot of people. I think he saw how crazy the market was and stuck with someone who's a known commodity and dependable, even if he's not anything great. Better him than some AHL scrub. It also might have been different if they had prospects in the AHL ready to step in but it doesn't look like they do. That of course is on Shero but it's a separate issue.