I have heard that and believe it. I lived from age 8 to 25 without and ACL and played 3 sports, skied at a high level and did just about everything else I wanted. I would "tweak" my knee about once a year, but otherwise the leg muscles compensated for the missing ligament.
I also think P Rich could be back if the rehab went well. I tore an ACL in March and was guiding rafts in June.
I don't know if it is harder to believe you tore your ACL at 8 or played sports without one. There is no leg muscle that can replace it.
I guess you are 25 now?