I too use the clutch pedal as a footrest and I was told that this was why the clutch return spring is a little heavy. My problem is not that of using the clutch but that I get an intolerable pain in my left knee when I have to sit with my knee bent for a longish period. This even occurs sitting on a chair at home. It is not a problem if I can stretch my leg out. There have been times when I have tried all sorts of positions, even trying rest my left foot above clutch pedal.
I have the seat as far back as it can go but, with my long leg (gamba lunga

) I still have to have my knee bent. With an auto I would have the space to stretch out. I suppose I could always buy a new PlusFour (CX generation) auto but that would impact a bit too much on my pension fund

, Besides I like the car I have.