I agreee with the OP's comments but what can you do. I ride my local trail everyday.
There are breaks in the trail about every mile to mile and a half and there are signs in both directions with simple trail rules. On every sign it says "announce intentions to pass" but it seems hard or immpossible for some and it is usually the guys in full kit on an 'UBER' bike. I cannot imagine why someone would want to make it unsafe to the point of actually endagering people while running the imaginary 'Tour' in their heads.
The stuff I have seen is sometimes just unbelievable... Example today I just cross a
street and am building speed on a slight uphill climb. There is an older woman up ahead wobbling as she is trying to gain enough forward momentum. Coming towards her is a couple walking and almost to the point of convergence. I slow my roll to let the walkers pass the lady. then I will simply announce "on your left" and pass her. A couple seconds before I make this move a guy blows by me unnanounced going all out, as he did not get stopped by traffic. He then passes the wobbly lady as the walkers are just about to walk by her. He barely misses the rider and the woman walker who has to jump aside. The lady on the wobbly bike is so startled she ends up in the grass.
I just shake my head and add this moment to the ones I have eperienced....
When I was in Drivers Ed in High School there were situations where you have to just "Brake and Hold." It's no different on a bike but some people just don't care.

I don't care that you don't care but your lack of caring can put us both in harm's way. If you wish to be reckless then that is your privelege. I just ask to not be a part of the accident scene...
Keep it safe, Please......................

Max Bryant