In theory what would this take

It's just to much money to be retained. It would be great for Edmonton to aquire him but 5 million a year to a player not playing for your team? I don't know of any trade that required that much retention

karlsson’s at 11.5 a season is worth a 1st, at 6.5 a season for 4 more while on a 100 point pace for a D man is worth a fortune. your looking at multiple 1sts and multiple early to mid round picks plus a quality prospect. more reasonable trade would be 3 mil retention (8.5 per season) for Barrie (4.5 mil cap dump) Puljujarvi (3 mil cap dump) 2 1sts.

Retention alone does not make it work then you offer a low first and a couple of Rejects

That is true but is San Jose keeps him they are paying 11.5 mil. If they buy him out it's more than the retention. So yes your loosing the on ice player but the owner is saving cash in his pocket.

Not saying it justifies the rention it's still alot of money to pay someone who's not playing on your team. Which is why I don't think it will happen, but they are going to have to retain if they want to trade him.

Saying that Karlsson is a 100 point D-man is such a recency biased opinion though. Barrie has just as many points as Karlsson in the past 4 or 5 seasons so using your reasoning Barrie is not a cap dump.

Yes Pulj is a cap dump but only for a couple of months and then you release him to free agency.

I don't think the trade happens, but if it does there is no way that you are getting multiple first round picks and a quality prospect.