Is it possible to design a section that favours one bike or the other? Absolutely. It's therefore essential that the sections either favour neither, or they balance so that 20" are favoured on some, 26" on others. Of course, people will always bitch that it's not in their favour, that the other bike would have been easier, but that's life. The bigger problem is that it isn't one person who lays out all competitions. I can imagine, especially at an international level, where a section layerouterer has more experience of one wheel size than the other, and unconciously puts a bias in. I think there's also a problem that riding standards are so high that sections in both red and yellow are both technically and physically demanding, so the results often have a leading group, a couple of other groups around the same score, then a number of high scores. Competitions should be a challenge, but trials in the UK cover everyone from the beginner to the fat lapsed rider to multiple world champions. Can we still say that National events should be like half a dozen world rounds? I don't know the answer here, just some thoughts for the mix.