I've just been reading through all the above messages with interest. I'm afraid I have no additional help to offer, just sympathy - because I am also suffering in much the same way.
Having been out of running for only 8 or 9 months, I started again and pulled a calf muscle. Having rested and treated, I tried again after 2 weeks and only lasted 2 miles before the other calf went. This has been repeated several times during the last 3 months. I have been to physiotherapist, I have tried warming up, I wear the right shoes, I walk/run very carefully, I stretch and roller afterwards. I still have the problem.
I would climb the walls if my calves would stand the strain! The only cause that I can think of is that I have recently started a new job which involves me standing for all my working day. Any further ideas?