About a month ago, I saw an article on "load management" in the NBA. The term was unfamiliar. To summarize, Michael Jordan usually played 82 games per season. LeBron James didn't, at least not the last couple years. The James method is winning, and not just in the NBA. I don't think the shift back to a 15-day Injured List for MLB pitchers will change much.
Players used to be afraid to go on the injured list. With one-year contracts, the looming possibility was to be phased out if his replacement played well. Wally Pipp, being replaced by Lou Gehrig, was the extreme case. Players played through injuries, in part because that was the expectation. Toss in that the guy that would fill in for him might not give the job back, and players played through pain. Getting to the playoffs used to get teams to the finals. Now, it gets them into a grouping of plenty of teams, all with a chance.
The player with a three-year pact? Missing three weeks gets him more healthy for later. If the season is supposed to run into mid-October or later? Some time off ranges from acceptable to good. The money is guaranteed, anyway. If a player is making eight figures, he’s unlikely to lose his gig by taking time off for a mid-range injury.
With pitchers, the willingness for a virtual healthy Injured List stint is more compelling. If pitchers "save 20 innings" for October, it can aid the postseason run. Will requiring pitchers to miss over two weeks, instead of merely a week and a half, greatly reduce injury placements? I doubt it, though I expect a case-by-case look to be realistic. For teams that are rushing toward 95-plus win or loss seasons? The stint duration shouldn't matter. One group of teams will be prioritizing October; the other 2021 and beyond. If a starting pitcher will miss 9-13 days? Sit him. Get someone else a shot. It boils to the teams in the 70-85 win ranges.
Executives seem to realize they'll use 25-plus pitchers in a season now. Some will be useful, with others counter-productive. The executive's future employment is based on guessing right on trades and free agency, and developing league-minimum talent. If he can't produce the latter, he'll be gone soon enough. The seventh or eighth starting option needs to be available, along with the twelfth or fourteenth reliever, or the executive might want to update his LinkedIn profile.
Owners want their players to stay healthy. More so, they want their chosen ones to make calling up talent from Triple-A less traumatic. If the executive is so committed to his opening day roster that he's unable to freely summon new talent, he's wrong for the job. It's nothing personal. It's business.
Might there be specific situations where a team would prefer to gamble that a pitcher can be back in a shorter period than 15 days? Sure. The Cole Hamels Experience, and the general randomness of the game, call into question whether a pitcher can declare himself ready for action. The keeping players healthy cat is out of the bag. Teams didn’t have dietitians, yoga instructors, and mental skills directors previously. Squeezing all the paste out of the tube is how teams get parades, now.
Load management is de rigueur in the NBA, and might soon be standard practice for some college basketball teams. The genie isn’t likely going back in the bottle. Developing more cost-controlled assets is what gets executives contract extensions. A team or three might have situations where they opt out of putting a pitcher on the injured list because of the new 15-day minimum. As committed as teams are to developing 15 to 17 usable relievers in a pipeline, I doubt the Injury List placements are reduced much, if at all, by the elimination of the 10-day stays for pitchers.