I just hit stage 2 last night, without yet snipping the frenum...I was sitting there for 20 minutes pushing with my fingers, thrusting forward, etc...it happened when I wasn't paying attention to it. Then I could easily feel the midline and what seemed like the passages on either side...
This morning I awoke to do my practices with a high pitched ringing sound in me (not just in my ears). I had noticed the sound beforehand during meditation...as if a TV was on. Sometimes it sounded like wind rushing through the woods. This time it was higher, stronger and centralized. When I'd move my head too far forwards, the sound would go away...or too far backwards, or to the side. Only when I was in alignment was it the most apparent.
Interesting stuff.
-Scott