Thanks for the responses everyone, sorry haven't been back my internet connection has been very tempremental this week. Will go through all those links, they look really interesting.
Some of them seem to be about permanent susceptibility to further concussion, ie that for example footballers who have a concussion, recover and then go back to playing will get the next one more easily. Whilst I have no doubt that this is true and is of great interest to me, I think on this thread I'm talking about something slightly different:
I'm talking about ridiculous oversensitivity as a PCS symptom, the kind that meant that I had to wear specially cushioned trainers (sneakers) for around 6 months because otherwise even walking was too much of jolt. A kind of sensitivity which would mean that you would not even consider returning to any sort of contact sport, but which is not permanent and seems to improve slowly (I can now walk around in normal shoes

and the jolts I do get seem to affect me somewhat less than they did )
This seems from what I have heard on here and heard from clinicians and others to be a fairly common complaint, yet little if anything is written about it anywhere. It seems odd that such a relatively easy to describe complaint seems almost unheard of whereas something more abstract such as 'executive function deficits' seems to get a lot of explanation....