I think I may have found the reason for my break-even run. Well, hopefully I have, anyway.

I've been playing from around 9pm-midnight UK time on 'Stars, which is 2-5pm USA time (depending on TZ, obviously).

I think combined with the Christmas tightening up (which to my mind is irrefutable - I've never seen 'Stars so tight since I've been there, and it was tight to start with) there is no surprise I'm only breaking even. I would be winning, but one major slip-up in a session takes so long to recover from in this 'siege terrain'.

So I tried staying up until 3am UK time yesterday (8pm US time) and things were a whole lot different.

Before midnight, I have found

* no talking at tables, indicates 'serious' players
* plethora of known nut peddlers (honestly, I have trouble finding a table where a 'known' TAG isn't present)
* virtually no all-ins

After midnight, I have found (to my great relief)

* tables quite chatty, indicates 'pleasure' players
* virtually no nut peddlers but instead gamblers
* people going all-in on TOTAL bluffs, longshot draws etc.
* people APOLOGIZING to each other for winning hands (e.g. cracking AA)

It's just a lot more fun. I'm seriously considering going to sleep for a few hours when I get home on some nights so I can play until early morning without incurring a sleep deficit.

I agree.

I recently started playing quite a bit between 12am-6am EST and am showing much better results, at least short term.

For about 6 months, I broke down all my play by playing times. My win rate was substantailly higher at certain times of the day (and on weekends).
Nights and weekends are by far the best times to play.