So it only took me 17 levels to figure this out.
Master of the obvious, me.
I need to thank Scott for dropping the very valuable clue that Neverwinter was intended as a co-op action RPG in my earlier post. That, combined with finally getting lazy with repeated click spam led me to this stunning revelation.
Holding down the left mouse button = automatic sword swinging.
I may have outsmarted myself at first by being influenced by GW2 and Wildstar, trying to pick my timings and utilize skills and dodge properly.
Instead of each button press getting delayed by some 200ms of latency, all the animations chain together and the mob is dead and flung away before my sword has even lowered again.
And a few other encounter skills still seem to fire through the basic attack, like the sweeping aoe damage snare, though I let up periodically to make sure my stun/prone skill carries out its animation properly and behaves.
The Great Weapon Fighter now feels like this:
Especially after picking up the pet cleric at level 16, and upgrading from a 99 damage +131 Power greatsword to 157 damage +331 Power greatsword at level 17.
It seems to have gone even further down the simplistic spectrum though.
Photo courtesy of Vaikoovery from Wikimedia Commons.
Used under Creative Commons 3.0 Attributon license.