As you may have noticed... Mics with XLR's have 3 pins... this is called a "balanced" system. Balanced systems will have 3 wires (signal +, signal -, ground), be it XLR's or 1/4" TRS, or 1/8" TRS (ref Korg MR-1). Most stealth mics, etc have a single 1/8" TRS connector... the tip is + on one mic, the ring is + on the other mic, and the sleeve is a shared ground. This is called an "unbalanced" system. Generally speaking, swapping between balanced and unbalanced is best avoided if possible. Lots of people swap back and forth and it generally works, but gear has impedance which are optimized when you use them as designed, and when you don't use them as designed they aren't optimized. I'll leave it at that.
It sounds like you have AT853's with XLR adapters running into a PS2 (balanced thus far), then are doing a balanced -> unbalanced conversion to the single miniplug, then splitting off to 2 TS jacks. Yes, you would be better off if you skipped this conversion. Get some XLR -> TRS adapters (ones WITHOUT impedance transformers), like these
http://www.zzounds.com/item--CBIAN424 Or you might be better off buying/making some with about 6" long piece of cable just so you can bend the cable in your bag.
At that point, you can probably leave the PS2 out of the equation entirely. Mics > adapter cables > Microtrack, and use the phantom power on the MT. I think the MT doesn't put out a full 48V, but AT's should be happy with whatever the MT is providing. The PS2 doesn't add gain, it just provides power, and that is available in the MT.
By the way... if this current setup works, it's not dangerous. But it's been written in several threads that using this same setup won't work correctly with some other mics. Some mics want you to tie the GND to Signal negative, other mics want a floating ground.