From my understanding and own experience I do find it weird, but in fact Ive only had this problem with my receivers catching wide open balls. They would stop and then take a second to regain speed, even with balls thrown in stride. Best bet is to change your speed.
For the most part, just set up your blockers before sprinting. Also, sweeps with 3 blockers out of a tight formation is automatic yards gained.... Everytime lol
Exactly my thought too. Great observation!