OR it could be that I've never "buggered" up a clutch head screw using a flat blade screwdriver and I see no reason to spend hard earned money on a tool I don't need.

I have one clutch head screwdriver I bought when I was a lad, first getting into body work and hadn't yet discovered that they aren't necessary. I don't think I've used it in 40 years. A flat blade works just fine.