Hmm, seems like with this many exceptions there is no hard and fast rule about contract amounts. Especially when we are discussing raw numbers and not CH%.
There isn't a hard and fast rule. It generally doesn't work.
The primary exception is Crosby/Malkin which just having those two is an exception. They won their first one with Malkin at sub-$1MM on the back-end of back-to-back SCF appearances and then couldn't get back there once Malkin got paid. It took until, like you said, the cap kept going up and for Crosby/Malkin to sign pretty team-friendly contracts in the context of how much their cap increased over their previous contract as Crosby MAINTAINED the same hit and Malkin's only increased by $800M.
Kopitar's hit went up by $3.2MM. Doughty's by $4MM hahaha.
That's a very good NHL player, or Kovalchuk if you are Rob Blake, that the Kings are down while we are talking NHL minimum for the difference between Crosby and Malkin's raises. Of course, Pittsburgh couldn't win on Malkin and Crosby's 2nd contracts but were able to do so on their 3rd since the cap continued to climb and they basically maintained the cap hit they had since 2010.
You're right though: there is no set-in-stone rule stating it won't work. It isn't surprising though that the Kings are in horrible shape while paying 11 & 8 since everyone could see the lack of cheap contributors in the pipeline and the team was pretty much maxed out from paying everyone else.
The cap will continue to increase so the impact of 11 and 8's hits will diminish but they are obviously not winning a thing at the current percentage of the cap they are taking up.
Crosby and Malkin were both 29 and 30 in their last two Cup wins. Doughty and Kopitar and 29 and 31 right now. We have to pray that these guys are still extremely good at-minimum--32 and 34. It can happen but the chances are highly unlikely that they are plus the cavalry arrives.
As for Chara, Boston couldn't win a thing during the length of that contract and finally won it in the last year of the deal once it wasn't such a drain. He then signed for a lower cap hit on his next deal!
Ovechkin finally wins it but, again, it is near the end of the deal when the cap has risen. Washington finally put it together and has Backstrom and Kuznetsov on great deals. I've gone over how many 1st round picks they have on that team when arguing with tomd about why the Kings need to rebuild. Regardless, everyone on that team and Ovechkin at $9.5MM or 11/8 at $10MM and $11MM?
You're right that it isn't "Can't have a $10MM contract" but that number is pretty much coming from Kane/Toews. The cap has increased so the number should increase. Even then, I understand that it is arbitrary as it could still work; however, it is going to take special circumstances.
Kopitar and Doughty weren't that special circumstance: not for their age and where the franchise was at. Now, even with their age, they could have been for another team but they were too old and the Kings prospect pool was too thin. Let's just keep our fingers crossed that the prospects can be impactful by 2022 and beyond. Some lottery luck next season would be a godsend.