There are some great things about summer: Long days, dry, fast trails, a cold beer when you get back. But there are also some irritating bits. Nettles, wasps and all the hikers and horse riders who suddenly appear when it's sunny and clog up the trails.
Now for the most part the trail centres aren't so bad - although you'll always get some eejit shouting at you for being on a recently built MTB only trail they claim has been a footpath since Tom Jones sang Delilah. Some centres have shared sections where you're likely to meet two legged and four legged obstacles on the trail. Then of course there's all the bridleway networks across the rest of Wales where hoss and hiker are free to wander, set up picnics or leave steaming piles of poo. They always seem to manage to be in the worst possible place round a blind downhill corner or at the start of the sweet singletrack descent you've sweated an hour to earn.
Now I don't want to sound like Uncle Bryn here, but however much of a pain in the saddle they're being, a little diplomacy goes a long way. After much experimentation we've found a long whistle (ideally with a rise and fall tone like a bosuns whistle on a boat or Star Trek) is far better for getting noticed without spooking people than a shout, or a cough or a brake squeal. For a start you can start it way back and keep it going until they notice. rather than a shout/bell whatever which they never notice if you do it far enough away and then panic and get offended if you do it too close.
Admittedly we've not tried a Vuvuzela yet, but we'd rather keep both hands on our bars while trying to brake towards a deaf dog and owner.
Once you've got their attention remember that they've basically walked or trotted into a kind of countryside coma, so keep all sentences and greetings short, friendly and easily understood. "Bike on the left/right please, what a lovely horse/dog/walking stick/day etc, three more riders behind." then go normally works for us.
To be honest you're always going to meet some cretins determined to have a fight over your right to be there, but as long as you are riding legally, just explain that you've a perfect right to be there and leave. You'll never convince them otherwise however irate you get, and you'll be miles away from their seething impotence in a matter of minutes anyway.
Don't forget to be nice to other riders too. We've all started somewhere and while some wobbler in the middle of a singletrack descent is a real pain, don't crowd them, carve them up or push past when you're likely to make them crash. You wouldn't have liked it when you started and they've got as much right to be there as you. If you can stop and wait till they've cleared the section do it, but otherwise just ask them to let you past when they get a chance to pull over safely.
Damn, I did end up sounding exactly somebodies dad there. Ah well, play nicely out there children and I'll be back with something more interesting soon I promise.