You wanted to know how it went? Ok.
After around one minute working on one side of my face I stopped. I looked like something out of a low budget slasher movie. Cursing, I finished the job with my DE.
Having done that I picked up the thing again to try to work out what had gone wrong. I ran it over the other side of my face and used it to touch up a couple of tufts the merkur had missed. I draw the conclusion that I had been too heavy handed, using too much pressure. Trying to be as light handed as possible and working now without any lubrication it did pick up the tufts with only slight damage.
So this is going to take time and practice. It was reassuring to note that the bleeding stopped very quickly. As I am on blood thinners shaving cuts can gush for some time, but not today. So I conclude that, horrific though the side of my face looked, it was just a series of very small, shallow nicks.
So, on non-work days I shall practice on a small area each day and try hard not to push the blade into my face. Hopefully, I shall develop the technique. Otherwise my wife will have the last laugh.