Not fun is it. I've used the edging tool with the wheels and while it is quick, it doesn't do a job better than by hand and you need to be careful about keeping the wheels and edges of the tool clean. I'm a fair way from being a pro painter, but have done a reasonable amount of painting and find that the steady hand method seems to work well enough for me. I reckon taping or using a backing board is just asking for trouble with paint getting in behind and makes the job more time consuming.
One of those TV reno shows had a pro painter as a contestant and while everyone else was taping up their joints, he was doing them all freehand, quicker.
Time to get the quality control dept up the ladder!