IWT requires click to move to be enabled.

For PvE, you want to push it selectively.
Push it once, and your melee toons move in.
If the mob moves, push it again to readjust your positioning.

For PvP, you want to spam the crap out of the key.
So your toons will constantly overrun the target and run back.
Which is very similar to the rogue swarming the target tactic.
You do lose a bit of DPS with all the movement, but the target loses some too... and if they're a caster, they'll lose a lot of spells entirely.

If you spam the key, or sometimes if the target dies as you push it...
Your toon will "run off".
You'll want slave independent movement bound.
So you can "down-arrow" the slave only, to break the movement.
You'll also likely want to have your follow key, very easily accessible.





You can play on your melee with the casters as slaves.
Have the healer and/or any ranged classes break follow.
And continue on with the melee.
If you have multiple melee, use IWT.

If you're driving your tank.
Or if you've only got the tank as a melee...
Consider using their Charge ability, once they're in range.

You should be able to heal, from any toon.
Because of Healbot/Grid/Vuhdo and an alphabetical sort.
With a Repeater Region over the whole frame, broadcasting those clicks to the healer(s).

Similarly, you should be able to IWT the melee...
From any window.

And really, you can bounce back and forth from one window to another...
And be in whatever window is most advantageous for a given situation.
Maybe the healer is a good window, because you're back from the fight and can watch for adds or a bosses phase/stage.
Then you need to move the boss or changes its facing, so you switch to the tank for that.
Etc.