The easiest solution to this problem is a tagging mechanism that forces teams to designate a contract or contracts as the replacement for the injured player, with the caveat that those who are tagged as replacements cannot dress once said player is off LTIR unless the team would have been cap compliant on the last day of the regular season with the tagged replacements + injured player all on the active roster at the same time:
-Tagging still respects the intent of LTIR, and lets teams replace their injured player for the time they are injured, including during the playoffs.
-Tagging doesn’t limit how teams replace them or the number of dollars/contracts they can replace them with, so GMs still have flexibility in trading, making waiver claims and call ups etc. if a player truly is out long-term.
-Finally, tagging eliminates the need for a playoff cap, which would be incredibly hard to enact given the CBA’s current construction.
Example: Mikko Koskinen ($4.5M) goes on LTIR a week before the trade deadline with the Oilers close to the cap. They trade for a goalie making $2M and a defenseman making $2.5M to try and make up for his absence, then tag those two players as replacements. The two players help Edmonton secure a playoff spot while Koski is out. On the last day of the regular season, the Oilers finish with just $10K in cap room.
Koskinen coincidentally becomes healthy game 1 of the playoffs; under the new rule, he can now dress, but the acquired D and G who were tagged as replacements cannot since all three players would not have been able to on the last day of the regular season.
With there being no cap in the playoffs, there is no negative cap implication for carrying that “dead weight”, and Edmonton cannot complain that they did not benefit from the stopgap additions as they did what they were meant to do- replace Koskinen for the time he was hurt. It would suck to give up assets for rentals who are only eligible to play for a few weeks at most in that scenario, but it’s a necessary evil to prevent teams from gaming LTIR.