Surprisingly no, I’d never sat on a bike before, aside from being a pillion a few times. I was chatting about it to the instructor before we started and I assumed I’d be okay on the whole balancing around the cones bit, but would struggle with the brakes, gears etc – in actual fact, and even more so when I moved onto the ironclad 500s we did our lessons on it felt so dissimilar to MTB that it wasn’t a problem. There was little cross over in terms of ‘operating’ them for me.
Where being a cyclist helped me was self-preservation instinct on the road and where being a MTBer really helped was avoiding that whole panic braking, going stiff thing when something goes slightly wrong – that’s what knocks off 90% of people who fall during their CBT, it’s not hitting something, there’s noting to hit, it’s panic braking or worse panic throttle!