I saw one of those, in 1985. It was an extraordinary evening. Here's a fragment of my review in Sounds:
Thrill to the sound of The Police reduced (?) to supermarket pulp, swoon to a couple of smulchy Lionel Richie hits, gasp as they massacre Debussy's Clair de Lune, wonder what he's saying between numbers.
It's like a drug. Everything, but everything, has a beat. During the 'slow, romantic' ones couples hold hands and the woman next to me dabs her eye with a handkerchief. Then in comes a 'fast, happy one' and people are dancing in the aisles, clapping meticulously in time […]
'The Long and Winding Road' produced lumps in throats. 'Two Tribes' was hilarious, Horn on helium. It's all too much for a cynical young hack - an evening beyond criticism, a sub-culture. I will, of course, deny that I stood up and clapped along to 'Wake Me Up Before You Go Go'. It just didn't happen.