I never repair a puncture on the road, but always repair it later at home, using a couple of spring clips to hold the patch on while the vulcanising solution is setting.
What I have noticed is that if I've done the job badly, the patch won't leak much until the pressures get lower. Then they go very quickly. Suggesting that it is not the vulcanising solution that is holding the patch on at 100psi, but mainly the force of the tube against the tyre. So puncture repairs on high-pressure tyres are just as good if not better than low-pressure equivalents.