Thanks for all your comments chaps. Much appreciated!
I have more info on the behaviour of my bike.
3 mornings on the trot this week, my bike failed to start whilst in neutral, and on those 3 occasions, simply pulling in the clutch enabled the bike to start, just like in the 'pre-easy start' days I guess.
Peculiarly, it behaves normally for the rest of the day when I return to the bike after work. ie starts without touching the clutch, as it should.
This morning, it refused to start until the clutch lever was pulled in (as is becoming usual) and off I went to work - a 6 mile ride.
When I arrived at work I switched off, then, as a test, and after 5 seconds or so (with the bike in neutral) I tried to re-start. This time it would not start! I Pulled the clutch lever and it started.
Tried again, same thing.
When the key is turned to the on position, like all modern bikes it correctly goes through its 'pre flight checks'. Fuel pump whirr, tacho sweep etc.
When the starting problem occurs, I push the starter and hear the whirring and clicking you'd expect, but just without the starter motor turning - which is why you can hear it I suppose.
This is different to when you try to start the bike in gear; when you press the starter, nothing, silence, - just as it should be.
So, I conclude that battery is fine, charging is fine and the starter motor is able to run, turn over the motor and start the engine. I don't think the ecu 'thinks the bike's in gear' since it behaves differently to when it actually is, ie whirring and clicking vs silence.
What is it about simply pulling the clutch that makes it turn over and start?
That's the puzzle. Interesting comments re the earth problem and the starter motor replacement.
I think a visit to the dealer is in order!