I can see how the marker/2nd man/cornerman/tailgunner system would work when you factor in fire roads etc, I guess it depends on where you are. Anything narrow, technical and downhill would mean the faster guys coming up behind the slower guys, putting the slower guys at under pressure
1/ You’d be surprised at how good the faster guys* are at passing. It’s racecraft for them in ‘local’ races, and is worth practising (passing and being passed).
2/ It gives them the chance to give words of encouragement to less able riders. OK, on a Trolls ride they can often be NSFW words of encouragement, bordering on the abusive and in some cases suggesting unholy and illegal acts, but that says more about the Trolls than the system.
3/ It’s a good system for a social ride of mixed abilities. As long as people know that’s what the ride is they can’t complain about the overall pace and abilities (although as above they might comment in unsavoury terms as a form of motivation).
4/ If you want a ride only for head down balls out fast as you can effort, go on a fast ride, or organise it yourself if the club doesn’t have one.
* Guys and They used to denote he or she interchangeably in the context of a trolls ride. Generally the lady riders give out abuse which is slightly more intense and personal.