an update -
I couldn't have been reading the thread very carefully because when I got home from work and sat down for my egg and chips, the first suggestion that came to mind was OrmRenewed's eschewing the cushion instead I made my self as low as possible, slouching back on the chair, chin just peeping over the table top, elbows level with my ears, egg metaphorically and literally on my face.
Mrs Stubborn was less than impressed (exactly as, I now realise, precicted by OrmRenewed; what was I thinking?
"What on earth are you doing??" asked Mrs S, "Is this something to do with the chairs, again"
"It was a suggestion I got from Mumsnet", I said, brightly, "IANBU, you know".
"You what?"
Before she went to bed Mrs S went from kitchen to living room and hid all the cushion she could find.
After she went to bed I pulled up a couple of kitchen tiles to see about these holes.
@SpringHeeledJack Hold that thought for I am indeed a colossus. Would you like to come into to kitchen and inspect my legs?
@gommummy go - so where do I find some of those rubber chairboots?