Does anyone use tricks to pull twisted-pair cables through under-floor cable trays, without pulling all the floor tiles? I was thinking about using some pull-string in a continuous loop, which runs down each cable tray. I'd tape the cables to the pull-string, and use that to pull the bundle of cables. But I am concerned that the cables would be moving under-floor without being in plain sight, and "something" might happen (e.g. twist/snag and pull on other cables).
I have low-voltage certified and BICSI people on-staff. But there are always datacenter tricks that they don't teach at the union hall. For example, basket tray (e.g. Snaketray) tricks are different from ladder rack cable-pulling tricks.