I've had a couple of students who make this chap seem like a spring chicken. They got through just fine.
Obviously they took a bit longer than the average 18 year old hot shot, but there was no difference between older students and one's in their 40's or 50's.
However, like most things, I suppose it all comes down to the individual.
Flying an aeroplane doesn't take that much skill. As long as you aren't a complete imbecile, then I've never had an issue with teaching people to fly properly. Co-ordination is rarely that much of an issue, it's between the ears that matters really.