I understand your point -- some videos are tedious beyond belief. But having made a few videos, I realize shooting and starring in a video is far harder than it seems, and video editing is difficult and incredibly time consuming. So I do my best to be patient and understanding when I view less-than-perfect videos that otherwise contain good content. I use the VLC media player and often run videos at 1.5 or 2.0 speed.
I watched the first Moenck and Mosher videos listed, and I did not perceive that they added "...1/2 the liquid AFTER the cook..." I agree that some of the fluid HP makers do add a lot of liquid, however, so perhaps what you watched different videos than I did. Dunno.
The Moenck video showed only yogurt and colorant being added at the end. She said she uses "full water" but she also warns about not adding lots of liquid. (edit: She does add sodium lactate and sugar to her lye water, however.) Mosher added other liquids at the end in addition to yogurt (sodium lactate and sugar syrup, if I remember right), but the amounts of these fluids seemed relatively small.
I came away from both videos with these key concepts:
Start with all ingredients that are all very warm but not scorching hot
Use a stick blender in moderation (pretty much like you would with any other soap making method)
Keep the soap as warm as possible throughout the process (but lots of extra heat is not required)
Minimize water evaporation
Add yogurt after the cook for added fluidity
Adding other liquids such as sugar syrup and sodium lactate seem to be more the preference of the soaper than strictly necessary. In the batches I did for the April Sous Vide HP challenge, I thought adding 1 tablespoon of yogurt ppo was truly helpful, compared with not adding it, but I didn't see any particular benefit to adding sodium lactate.
I also realized these "fluid HP" techniques cannot possibly be the intellectual property of one person. With the exception of adding yogurt, the "fluid HP" method is very similar to the method I've come up with on my own to make no-cook liquid soap paste, especially when I don't add extra glycerin. Adding milk products has been around for awhile too -- for example, Ponte Vedra Soap has had a nice rebatch method on their website for years that adds powdered milk for added fluidity. (Which makes me wonder if it's less about the yogurt in particular and more about dairy in general.)
