Hey Guys
I know its bad form to jump on forums and post links to products and stuff but I was searching around to see what was on the net for hamstring injuries and rehab and found this, I think it may be of use to you. My name is Lauren, I blog at LaurensFitness.com, my Dad has written an ebook on Hamstring Rehabilitation, it's pretty comprehensive, hes pretty experienced in the industry.
I don't want to sell it to you so just check it out yourself. Here is the sales page for the Hamstring Rehab Manual, which we had to make for clickbank....and you can also go here which the bertolacci.com.au website and check out more Hamstring rehab info for free, or head to his blog at loris bertolacci
OK I know a lot of info there but I reckon it might be exactly what you are looking for, how to stop hamstring recurrence injuries. If you don't want the ebook there is plenty of info on the bertolacci site! Hope it helps.
Cheers