They patches DON'T shake differently.. they're all the same!!!
That's your problem.
There are 3 types of patches:
The type that hardly shakes that has no pokemon. The type that shakes a little bit that has a certain number of species. The type that shakes a lot that has a different species from the former.
pretty sure you're wrong. when you start chaining you have to pay attention to the shake of the grass before you run into a pokemon. If it's the pokemon you are looking for, remember the shake and look for that shake in the future. So let's say you're hunting for Farfetch'd. The first patch of grass you run into is the slow crappy shake, but it's a Farfetch'd. Now you need to look for the slow crappy shaking grass to continue the chain, not the vigorously shaking grass.
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