I finally got my flying an surfan pikachu

still. what you say makes no sense

bulba- Get rarer pokes by timing

Serebii - bushes are just a visual game, they will go by the odds. You cannot affect them

I think you're still misunderstanding.

Let's put everything at 3 tiers with 2 subtiers.
1. !
2. !
3. !!
4. !!
5. !!!
6. !!!

The percentage chance is the chance that you will either get a Pokemon, or move to the next tier in its subtier (5 -> 6). However, the timing may change the main tiers (2 -> 3).

We're not saying you'll necessarily get rarer Pokemon through timing.