It's all part of the 'fun' of training for a Marathon. The stresses you put your body under, the psychological battles when your legs have been run ragged.
There should be a focus on balance, the non-runner sounds like he's got it right. Non-pressured running, no expectations, enjoying it for what it is. GOAL - to get round.
I had a poor showing at last year's Paris Marathon - no way would I have pulled out, just because of a niggle or 2. I believe with all the work put in - even if you have a few weeks off beforehand to rest injuries - get them treated, you could still surprise yourself on the day.
Even though I've mentioned times to Ash, 5hrs is my goal in SA. It all comes down to the day - it would be nice to achieve that, but to focus too heavily on time adds a pressure you don't need. It's a long haul over the Winter months - again it's balancing enough rest as well as the hard work.
You stick in there Steve - I'm sure you'll enjoy the experience.
MM