After some suggestions on the MGOC forum as to my the clutch bite point seems very close to the floor I thought I would remove the pedal cover in the engine bay and investigate.
I was surprised how much play there was in the pivot at the top of the pedal joining the clutch master cylinder. There was nearly 4mm of slop which translates to nearly 20mm travel at the centre of the foot pad.
It can be seen from the pictures the oval hole and the very worn cotter pin. I put a bit of weld in the hole and filed it out carefully to fit a new pin. Play now is reduced to less than 1mm.
I went for a quick test drive and there is a very noticeable difference.