A fool and his money and all that.
Had a great ride today, got through/over a stream I would usually refuse at but noticed that the chainset side had worked a good 5mm further into the BB. Clearly I had not used a torque wrench and had under estimated 55Nm or 480 in lbs to do up the main 8mm nut. I did wonder why the front mech needed regular readjustment in middle ring as chain kept magically moving and catching cage using non extreme range gears in block. Never occurred to me at the time the whole chainset might be moving further in!
Anyway stripped down, splines all perfect (lucky), regreased and done up really tight and looks like this now. Will keep a closer eye on this for the next ride and take 3 and 8mm full length allen keys.

Has this happened to you, or am I the first chap to be too careful/ginger with an expensive bit of kit?