Does the speed awareness course make a difference?

I passed my driving test first time (with the chief examiner in the back assessing the examiner no less) after 14 one-hour lessons. That was in 1992 and I've always considered myself a sensible driver, having never had so much as a speeding ticket.

That was until February this year when a letter arrived from the Suffolk constabulary. I'd been caught doing 35 in a 30 zone through the rural village of Yoxford on the A12; a crime of which I was blissfully unaware.