Well, against my better judgement I went along to the Trafford 10K this morning with a bit of a 'hope for the best' attitude, which was very ignorant of me but....
MASSIVE PB! Been waiting three years to beat my old best of 38.39 in 2010 but the sixteen attempts between then and now have pretty much all been sabotaged by the dreaded shin-splints. No pain whatsoever today, good conditions flat course,, and the months of training saw me home in 37.52. Really really chuffed with it and got to say, it's a massive confidence boost ahead of Paris! 
I'm most certainly not going to forget yesterday's episode though, and am taking it as a huge 'warning shot', and am safe in the knowledge that I've a fair bit of 'prehab' work to do between now and April 7th. I'll certainly be trying the barefoot-walking-with-toes-up you recommended Tricky Dicky.
Oh, and I got to meet Ron Hill too, who was there as an ambassador for Brooks who sponsored the event. Only downside to the day was that it was bloody cold and it took 20 minutes for my hands to thaw before I could untie my car key from my shorts (I tie the drawstring through the key, double knotted)! Must have looked a bit suss seeing a fully grown (well, as fully grown as you can be at 5ft 7) bloke fiddling with himself for a prolonged period in the car park!!
Weedy - regards keeping a training diary, I've kept one the past few years and have looked for patterns as you suggested but can't find any common factors, that's what's made it all the more frustrating! 
Marathon Maus - the Garmin 110 is a quality piece if kit! I'd be lost without mine and it's so easy to use!
James - good news with the injury! 'Proceed With Caution' should perhaps be the manta for the next few weeks...?