Kovalchuk is eligible to return for the 2016/17 season that's what this conversation is about.
Hall could not retire from the oilers and go play in Europe for a year and then sign with the penguins. If you wants to retire and go play there for 5 years and then sign with us for the 20-21 season, he is more than welcome to. What your implying to try and make your point is ridiculous and wrong.
Oh, I thought you were referring to him coming next season prior to his 5 years being up. In that case, this is indeed a pretty senseless thread to create based on rumors about two seasons from now. The variables involved (our cap situation, our forward group, etc.) make this really difficult to gauge. For the record, I don't really want to see him here when he's 34 or whatever and locked into a 3 or more year contract. Irregardless, you think the GM or the Oilers would say, here, go retire, play in the KHL for 5 years, and come back, I don't need the assets to improve my team at all? Do you think any GM would sign off on that, let alone all 30?
edit: His most likely return date is when he is 35 when he doesn't need anyones approval, apparently, and by then, who knows the make-up of this team.