Return to running after suspected stress fractures

I completed my first tri this year, an olympic in early June. Yay me! Unfortunately, I really did not train over a sufficiently long period of time and ended up pushing too hard, too fast on the running. I ended up with suspected stress fractures of the tibias. I say suspected because my ortho did not go through the time / expense of bone scans or MRI. He just looked at Xrays and manipulated my lower legs and had me do the one-leg jump. I also concur with his suspicion that this is likely a stress fracture. I have had compartment syndrome (and associated fasciotomies to resolve it) and shin splints and the pain here was very localized and tender on the bone itself, not in the muscle. He wanted to put me in at least one air cast for the more painful leg but I promised to lay low on any activities that hurt for 8-12 weeks. I'm at week 8 now and looking forward to returning to training. I have continued to swim and have significantly improved my biking (at least something good came of this). I also have continued my strength program. The only exercises I had to stop was squats and leg presses. It is odd that leg extensions and curls did not cause any pain though since I thought they would exert a lot of bending forces on the tibia. I finally did some light squats last week just to see if things were healing and had zero pain. Can anyone recommend a good "return to running" program? Historically I would do no more than a 5K run and a total weekly volume of ~10-15K. The 10K run during the tri was simply double my normal load and I must admit my running form really suffered after a long swim and bike. I am aware of the 10% rule and of course plan on implementing that going forward to avoid this (yeah, even grownups ignore the "rules" when they think it won't happen to them). In terms of a return to running, I'm simply not sure what volume to start at. My cardio fitness probably far exceeds what I should be doing for bone/tendon/ligament healing since I have actually increased rather significantly my aerobic capacity by biking during my healing. In addition, I'm concerned about truly knowing what caused the probable fractures. Yes, I did abruptly increase running volume and know suspect that is the primary culprit. What I'm also wondering is whether my weight or something else may make me susceptible to getting them. I have a background (10+ years) in strength training and body building and so tend to be rather heavy in weight for my proportions (am 6 foot tall but weight between 220 and 240). Does that extra weight mean I need to do something different (i.e. more cushioned running shoes, etc.) to reduce the impact or do bones grow stronger to account for that? I have seen and read here on BT of heavier runner who can successfully run much longer distances than I. My ortho asked if I was getting enough calcium and I assured him I do since I drink at least a gallon of milk every two days (I'm a big milk lover!!!). Anyway, any advice anyone can provide would be greatly appreciated. Just want to play it safe so I don't take myself out of the game any longer than necessary. I've pretty much written off 2008 for any further running sports and am looking forward to return to tri in 2009.