I have often wondered this myself. I would genuinely love to follow along with the folks who say they never wait more than 15-20minutes for anything. Do they have a step-by-step touring plan? (I don't want to do that, so I check that off my list as a possibility) do they have a fuzzy recollection of the waits they've actually encountered? (maybe 15 min is an exaggeration that I will never be able to match) do they only go for the first 3 hours, then have a 4 hour resort break, then ride non-headliners on return? (I've never followed this pattern, maybe it's the ticket to no-line success?) I already know I've seen many of those people say that they do ride headliners, so it's not just that they spent all day whirling on the teacups
I have never expected to achieve a 20 min max wait on everything at Disney. I have used legacy FP, FP+ and internet tips for minimizing some waits where I can, but I've never managed a whole trip with 100% lines of 20 minutes or fewer, nor I have ever had the expectation that I *could* do that. I think I probably waited over an hour for Space Mountain on my early trips and 45-60 minutes isn't at all unheard of on my other trips for a few rides. 30ish is common for me. If I were wealthier, I'd surely invite one of these experienced DISers on my next trip and ask them to be my personal guide!! (no sarcasm - I really want to see it in action, I can't imagine it)
Our Touring Plan was mostly half days, which is why we never waited in line. HOWEVER, we would tour that way with young children in the heat of June/July (when we have to go) anyway.
We did wait more than 20 minutes for RNR, but the ride broke down and we never rode it.
So our plan was rope drop, FP+ kicks in, brunch/lunch ADR, maybe another FP+ or no-wait ride (Tiki Room, we love, teacups, we love)...go back to the hotel. Rest, eat out somewhere to meet characters (so we aren't doing lines or many FP+ for those). Go to sleep
So for us, the key was Rope Drop, using the FP+ we were allowed on long wait rides AND paying more to have some experiences outside of the park (character meals and a pirates and pals cruise so we weren't waiting for fireworks)