You are right. My Sifu had the fortune to study under 3 different students of Yip Man. (Wong Shun Leung, Chu Shon Tin, Moy Yat). He notes that each had slightly different flavours, but for the most part, taught the same. I think too many people get caught up in the differences, and forget that the differences are largely caused by personal preferences rather than secrets. I also feel like too many people get caught up in the "concepts" of the art, and forget that the techniques are of equal importance as well. Hence my favourite quote "Stop reciting theory and hit your target." That's not to say theory isn't important, it is, but so are techniques, and mastery over them.
As a side note, try using Gan Da vs an uppercut instead of Gum Sao if the person is very strong. IE: person punches with a left upper cut, you intercept with left Gan on the inside of their forearm, and turn them so you have access to their outside gate.