I wonder if the message is more accurate, since some of the pokemon you knock out could just be normal wild spawns and not considered part of the outbreak
See that's so odd to me because everyone I know does the 60 method just purely because that's the odds given on serebii! I wish I had been doing it your way the whole time, less counting for me haha
I had always wondered if that was the message we were looking for. Early in the game I caught shiny Azurill and Tauros with no sandwich powers. I even caught a shiny Snubull in an outbreak a few weeks ago and all I was doing was clearing them out of a cave so that I could make Torchic spawn.
I've already been hunting at the point of the third message anyway. I noticed that, in general, each message appears every 25 (or so) Pokémon defeated, so the theory is, if I just knock out until that third message, I don't have to count (and, thus, remember what number I'm on/risk losing count) I can guarantee that I'm at the highest odds. It usually means spending just a little more time knocking things out, but is more consistent, less troublesome, and more "autopilot" friendly.
I can’t bother to count them all and then there’s like 60% of outbreaks that happen in an area where the Pokémon spawns natively so keeping track is impossible. The message always worked for me.
I think that it's a good way to help so then you don't have to count how many pokemon you KO that way you can immediately start the respawning process.