I agree, I think there are other factors because coaches may not want them back unless they are 100%. Generally though I try to consider the severity, how much time has been lost already, position and strength. I liked using minutes of play to progress them back to play. Not an exact science but as long as they stay full strength (repeated testing at 90 and 15 deg) and full ROM, keep going. Not a deal breaker, but if you have Catapult data or any of the other fancy gizmos you have more data to make decisions. Can be a blessing and a curse though. If you’re talking a higher grade, then following a jog to sprint progression. A lot will be feedback from the patient, as well as what we can see when they go through the progression. Both land and pool if you have the ability to. Overall, sprinting and eccentrics are going to be your best friends for hamstring strains.