Not sure if this means anything, but we run a fall league in Iowa. They play on the weekends and practice occasionally during the week. It usually has the top players in the state playing in the league. In fact, over the past twenty years all but one player from the state that has been drafted out of high school has played in this league. That includes a first rounder, several second rounders and many more.
We always have some football players in the league. These are usually football players that believe their future is baseball. One year we had 5 players that were all starters on a state Championship football team. They would play football on Friday night and play baseball on the weekend. I'm sure it was a grind for those kids, but all 5 went to DI colleges to play baseball and one ended up playing a bit in the Major Leagues. The schools they went to were, catcher to Baylor, Shortstop to Notre Dame (and MLB), pitcher to Wichita State, Outfielder to U of Illinois, pitcher to U of Nebraska. One was named the football player of the year in Iowa. The coach of that state championship football team was the father of the catcher who went to Baylor.
All five were scouted in the fall league and seen by the recruiters from the colleges they chose. So without saying it was a good thing or not, it worked out well for those kids. In fact, I think it really impressed the baseball recruiters knowing these kids just played a big football game on Friday night and here they were playing fall baseball on the weekend.
I'm not saying I would recommend playing football and baseball at the same time, but if we are in favor of multi sport athletes we are going to get some of this. Most kids know what they will play at the next level and will do what it takes to accomplish that.
Good or bad? I don't know, guess it kind of depends on the results.