Likely won't make any progress on this. Saying "volume is irrelevant" is equivalent in the trading community to saying, "there's no such thing as God".
I use it in conjunction with the double sto on the other tf's to confirm or negate a signal. There is one reversal signal when I get significant divergence on two adjacent tf's. And more generally, it gives me a sense of momentum dynamics across the tf's.
What you described is exactly what I am doing but with the MACD instead of Stochastic... in conjunction with S/R and price action patterns at said s/r. I am still wrong lots but its a learning process. I dont believe that a losing trade is because of win/loss rates or probabilities. You lose because you made a mistake with reading the market... simple as that. You missed something somewhere.
Don't be hard on yourself or too critical if a trade fails. There is no such thing as a sure trade. ANY signal may or may not work. Looking for perfection can confound and frustrate you. The point is to profit, not to be perfect.
I hear you, I still struggle with that but its coming along. There is this idea in trading that trade signals have a probability of success based on historical results.... I dont really view the market like this at all. Every trade is a completely unique situation and must be read in the context of the current price action along multiple time frames to gauge how far a certain bounce / drop will go. All comes down to momentum and what the market is setup to do. I believe that these volume people may have something in what they are saying but there are easier ways to read the market then trying to look at volume and bar by bar relationships.
No two people trade the same because no two people are the same. We each have to find what works for us. If it works, then what someone else thinks about it is irrelevant.
I can tell you that price & volume works for me. I am 4 for 4 successful trades today thus far. I was told by the trader who taught me this that other traders would react negative. I know what I know and it is best just to keep it to myself. ES P.S. Is it easy...hell no. Trading takes practice and I consider it an art.