Pitch inning 1, taken out, then go back in in inning 5

coaching question for you. have you ever heard of pitching a kid an inning then holding him off for later in the ball game due to pitching limits and perceived game management?

this has been a trend on my son’s 3/4 team. some of the kids throw pretty hard so my concern is their arms. obviously getting warm then cooling off then getting warm 90 minutes later.