I think ppl need to have incentive for rushing something or doing anything? tml is one of those options...
If you scout, you can be prepared, as long as you choose a normal teching process(unless you are being outplayed)
I'm a casual noob , but also found support tml early is fairly expensive.
Be a shame if tml turned into mercy
got to be said though, with the height problem, that is when making 20 tmd becomes a problem:
https://forum.faforever.com/topic/7834/tml-height-needs-to-be-lowered/3