Funnily enough mine's started behaving like that recently - it's definitely not a trait of the bike because it didn't feel like that for the first 35,000 miles.
Exactly the same symptoms as you - off throttle or on the brakes it feels like there's a big notch in the steering head bearings - doesn't want to let you turn the bars from straight ahead. Then at some point you overcome the resistance and the bike falls over into the corner. On the throttle it's much better.
I've been putting it down to wierd tyre-wear - I've got aggressive knobblies fitted which have done three rallies and several thousand miles, the rear is square and the front is probably a bit odd as well. Unfortunately I'm trying to use up my stock of part-worn tyres, so I'm probably not going to have a 'new tyre' comparison until the spring.
I don't remember it ever feeling like that when I had the OE Tourances on, but that was over 30 months and 30,000 miles ago
. I do remember not being particularly impressed with the life of them.
The really obvious one - have you checked your tyre pressures?