I'm American and I've never done cut-and-switch. Since I was a kid, I've always knifed with my left and forked with my right. Never understood why people feel the need to cut meat with their right hand. So weird to me.
Presumably because cutting meat takes more strength and/or control than simply holding the meat still. It seem reasonable to relegate the latter to your non-dominant hand.
I find getting the fork into my mouth to require much finer motor skills than the simple sawing motion required for cutting. I'm with GP. I just keep the fork in the right hand and cut with the left.
As a kid, I was a cut-and-switcher, so maybe cutting with the right was more natural, but it definitely didn't seem hard to make the switch.