@raghav,
@Basilico,
@kangaSue,
@Janice Hargreaves - Hi all one more time - well, apparently this pose has stimulated my thyroid quite a bit, and what started out as very relaxing and helping me to sleep, has ended up causing severe insomnia due to hyperactive thyroid. It seems that the increased blood flow to my thyroid has perked it up. I have been taking 130 mg. of Naturethroid for many years, and suddenly it's way too much for me.
This insomnia has now been going on for 5 or 6 days, I'm working to calm down my thyroid, playing with my NT dose, started taking lemon balm. It's crazy. It seems there truly is
NO REST for the wicked!

(at least there's certainly no rest!) I'm sure that's my Catholic heritage speaking out there, but that's what it feels like. The irony is extreme, what was supposed to be (and was, initially) so very calming etc. is now making my sleep worse than ever.
So - this would explain why this pose when done at night in the early days caused insomnia. And then after 3 or 4 weeks of doing it, it just caused insomnia regardless of when I did it, so I've stopped it.
I don't know if it would affect people who do not take thyroid meds in the same way. I hope it doesn't hit any of you this way .....
If someone has a low functioning thyroid, the pose might be a good thing to do as long as they know what's going on -----
My chiropractor told me that the thyroid is regulated by blood flow, so it would make sense that this pose would stimulate the thyroid.