Thanks Kirk,
I've been told before that the Decathlon could be tricky, but couldn't see why.

Now I think I'm beginning to understand the difference between centre of lift and centre of gravity.

As I see it, - the centre of lift (neuteral point), is inherent with the design of the wing, and stays put as the permanent pivot point of the wing, whereas, the CG position can be moved, giving the aircraft a nose up, or nose down, attitude. ( back for nose up, and forward for nose down).

I realise that my perception is a bit simplistic, but is it basically correct?