German v English
I used to ride often with German holiday makers who had travelled to Wales to see the countryside. I cannot remember one who was a 'weak' rider - they mostly had been well schooled to ride. What they envied of riding in Wales was the lack of formality. Mind you riding at speed a Welsh cobby horse, over pot holed, uneven, boggy ground covered with heather, did call for a certain level of riding ability. Still it only took a day to show them how to cope. I enjoyed riding with them.
Ps Thinking back, there was one Dutchman who did withdraw early in a trek - maybe because he could not cope with the English trot - I never thought to ask him.