We need to broadly forget age based competition, design our events and then have the age stuff sit on top. Instead we always work the other way round.
That I totally agree with. Its ridiculous to think that after 40,50,60,70 years of life the thing which determines my orienteering speed is my age. Even more so on the years where you hop from one class to another - that people born a few weeks apart can be in different classes. Even with juniors how long you've been orienteering, puberty, etc have a much bigger effect. Add motherhood and menopause into the mix and its clear that age classes are crazy. But then you say:
Well it's not really. You just have 2 short green legs and an orange. It's a bit meaningless and people end up dumped on it because the other categories don't fit whoever's left over. I've done the ad-hoc twice and it was just not really fun as it was a bit pointless.
Surely this relay class is actually the epitome of what you want. Put relay teams together based on who is going to enjoy those courses / have fun rather than arbitrary ages. At the end of the day all orienteering is pointless - you run around with a map and eventually end up back where you started, tired and having paid for the pleasure! If you mean "i didn't win a medal" or "my medal doesn't feel like a British Champion" - thats 95% of orienteers every week. We do it for fun not win. Running relays can be fun. I suspect my club captain would think (but is far too tactful to say), "if you don't want to be dumped in the leftovers category, get better at orienteering!". Personally I'm always happy to be dumped there as it means there's less pressure on me if I make a mistake.