Having had an acl tear myself I did lots of research on what's referred to as the "gold standard" surgical repair. This changes over time as they've refined techniques but I believe most grafts these days if they take and heal properly, create a much stronger ligament than the original tissue making it less likely to tear again. I think the key is the acute stage and mid term recovery injury management by the physios. Athletes have a much quicker response time than us mere mortals.You're right about the psychological aspect of the injury. I expect him to be out all season to be fair as 9 months takes us to June which is when I suspect he'll be approaching match fitness.