Bit the bullet yesterday and purchased 2 new Goodyear NCT 5's (to match the rears) for £112.00 fitted including stick-on concealed balancing weights
The tyre Gaffer said my Michelins were probably the most evenly worn old tyres he'd seen

they'd been on for at least the 2.5 years and 20K for me and were worn perfectly even across the tread.
It used to pull to the left so I assumed the tracking was out but now it tracks straight and true with the new boots on

the steering has lightened up (obviously) and dare I say it's a tad quieter too
Interstingly whilst it was in the air I looked at the rears and was shocked to see the outer 33% of both rears is wearing unevenly and markedly

not getting near the limiters but worse than I would like. The current rear sussy fix should straighten this out but it would explain the "strange" rear handling for sure.