When did this become a trend?

[Thunda_Cat_SMASH]

But claiming that promoting effective and skillful healer play through the use of all healer abilitys encourages this sort of bad play is a stretch.

The vast majority of healers I've seen that demand the tank sit in tank stance when the extra enmity and mitigation is meaningless have always been CS focused healers, in my experience. Healers that are focused on healing have no difficulties handling mechanics and keeping the party standing, but even with a proper CD rotation, many CS healers I've seen have demanded pointless excessive tank stance uptime.