I've seen it--when I was an RCA, the regulars in my office would never discuss what days they were taking off or going on vacation--just normal, conversation stuff-- because other regulars would then put in leave requests for those days to block them. Sounds crazy, but I saw it in action and it definitely happened.
And when RRECS first started, the carrier who worked next to me turned the volume on his scanner very low, so other carriers would not hear him when he entered WSS, so that wouldn't alert them to enter it, too. He has since moved into management
And one of the enormous problems with RRECS (I think, at least) is carriers who are close to retiring or bidding on other routes or moving into other positions who just stop doing the RRECS entries to mess with the evaluation.
And the number of carriers who have contacted me over the years who want to file "grievances" against other carriers--it was crazy. And all the sweetheart deals that I've found out about over the years (and those are just the ones I found out about!)--in my experience, there are way more carriers ready and willing to screw over their fellow carriers for their own benefit and even just for the hell of it.
If your office isn't like this, then you are very, very fortunate.