That second link is a gold mine. Thank you so much for sharing.
I've known how to do the basic BTV/VTO for many years, but it wasn't quite enough for me to equalize pressure while diving (without descending very slowly, I suppose). Just a few minutes with the techniques on that page has already improved my ability dramatically.
Cool, hope it will be of use! I freedived for years before trying scuba, so for scuba I have no issues. With the head up and all air going there, my VTO is good enough.
But for freediving with the air going towards the stomach and much faster descent it's still a bit tricky. One thing is if I'm not equalizing quickly enough, no amount of force I can muster will open the tubes again without actually doing a more classic pinch nose technique. Doing a classic equalize you will often "overblow" air in and can descend a bit before needing to equalize again. But with VTO you're only equalizing to a perfect balance so will need to make sure to keep equalizing to not get under pressure. But of course not as much hassle hands free, I try to just do click-click-click continuously, almost every kick down to remind myself to keep it open. But yeah, if I get too much under-pressure I'm not able to open it again hands free.
I also feel head angle matters a lot, so trying to not bend the neck too much to look down, but instead swim down while looking "straight ahead" instead of where you're actually going helps for me.
I've known how to do the basic BTV/VTO for many years, but it wasn't quite enough for me to equalize pressure while diving (without descending very slowly, I suppose). Just a few minutes with the techniques on that page has already improved my ability dramatically.