I practice Mahasi noting but as I rise through the nanas I tend to shift to open awareness, then shifting back to noting if my mindfulness gets affected by sloth/torpor.

I regularly get into high EQ territory, my concentration getting pretty consolidated, noticing the field of awareness, resting there but gently being aware of the arising and passing of the sense gate objects.

Doing this type of practice one is getting into vipassana jhanas, which have different qualities in terms of their affect on the attention wavelength (e.g., narrow, wide, expansive), feelings of piti in the body, different degrees of pleasure, etc.

During practice I was residing in high EQ, sort of at the level of the field of awareness, and I was actually doing some "aware" thinking about the different splits that have occurred at the Dharma Overground over the years, when I got a sensation between the eyes that seemed to spread down into my limbs, I felt even quieter and had some light pleasure in the body, I felt even more "isolated," so to speak, even more equanimous, and I wondered, is this a soft samatha jhana?

I tried shifting attention to pleasure in the body, which cause a short gush of semi-sickly sensation to arise, but then I started thinking: "Is this a soft samatha jhana? How would I be able to tell the difference between it and regular dreamy, pleasurable high EQ? What is the qualitative difference between a vipassana jhana and a samatha jhana? And do pre-stream vipassana practioners occasionally shift in samatha jhanas while in EQ?"

I didn't have an overwhelming experience of bliss but then I seem to recall others saying that the degree of bliss is dependent of lots of factors and that one can be in the 1st samatha jhana with great variations on the levels of bliss.

I will note that a few nights ago I got what I think was a stream/1st path near miss. I was experiencing a lop of flickering/pulsing. At one point it deepened so much I felt my balls shrivel, but then the pulsing abruptly passed. I don't think this was path entry because most seem to know it once it's happened, and I haven't gotten any cessations in my subsequent sits, don't feel like any fetters have dropped, that my Watcher/Observer is any less embedded than last week, but it is possible that the near miss might of slightly powered up my samatha. Just a hypothesis, cause I'm not even sure that what I experienced today was the 1st samatha jhana.

It's a goal in Taiji the ability to command at will the ignition of the Niwan (center of the brain, at eyes level) and let the energy pour to the arms/hand. But that's pretty advanced. I haven't experienced that, but general energy flow in the heat, pulse, vibration and wave modes. Some of them are amazing but none of them are pleasurable. So what you experienced was probably some fusion with vipassana jhanas. 
Many people here in DhO chart all meditation experiences within a two-dimension map: vipassana (X axis), samatha (Y axis). In my (pre-SE) experience, moving in any direction during the session in this 2D map is the standard modality. In fact, if that drifting doesn't happen then you are probably applying willfulness, which is highly unrecommended in High-EQ. Check about that at Shargrol's post compilation or Daniel's MCTB2 chapter in EQ (I did a summary of it in my practice log). Also check Niel's practice log for more about the willfulness/knowingness thing. Regarding 1st samatha jhana in EQ, it could well be "4th Jhana - 1st subjhana" in Daniel's terminology, or alternatively "11 ñana - 4 subñana".  

Metta!

https://static1.squarespace.com/static/5037f52d84ae1e87f694cfda/t/506fcc5c84aefb9a79a610b3/1349504092518/Pathways.jpg

https://www.integrateddaniel.info/mind-maps-full-size


Fun stuff there....check it out.
There is a lot more territory in EQ than meets the eye.....so move your high EQ down to Medium EQ if you are thinking about stuff and hanging out.....high is brief; right before the cessation. (Depending on how you like to define stuff)
Good luck,
~D