I missed this one - fresco conference is better for fresco related posts.
"unmixed powder" - what do you (they) exactly mean by that? Is it a pure pigment or a dry tempera mix of a sort? as well as "mixed with water in an 8 oz squeeze bottle" - is it suggested to be used from the bottle as is. if yes for what application?
As i gather from your post and profile you use it directly on paper? If that is the case it would be no good for fresco since it would have to contain a binder, otherwise it would just fall of the paper, am I right? (they may call it liquid fresco paint, but I doubt it is - it is a nonsence by the definition - something like "organic oily butter for manual transmission")
For fresco you need just the mineral (pigment) itself.
The wall (lime) is the binder. Water is used as a vehicle to help you move the pigment around. Any binders and/or additives will kill or weaken the process and the wall will separate the paint off itself, which (paint) will fall from it as the plaster dries. Fresco does not leave any space for "improvement of its basic technology/chemical reaction". Any alterations will render it into something else. Forgive me an analogy - H2O can be mixed with stuff and result in coca-cola, for example; you can drink it, but I doubt it would improve the fish tank flora/fauna if we woild be to replace the water there with coke.
However I am looking for better paint for my renderings, can you give me some advise on it - tube tempera/casein/acrylic paint has more "glue" in it than it does have paint so I am looking for a fare substitution to making my own egg tempera each time...
Does this "liquid fresco paint" worth a shot? Currently I mix my pigment paste (pure pigment ground with distilled water into a thick paste) with whisked egg white and winegar - but it takes half a day to make paints every time i need to do a 12X12 or so rendering and which (paint) never lasts long enough to be used again. So most of the time I just grab whatever paint is on hand in my mural box and curse...