Optimization flags arduino 1.6.5 !

1. I have been reading this:
http://www.instructables.com/id/Arduino-IDE-16x-compiler-optimisations-faster-code/?ALLSTEPS

2. Page 6 states that platform.txt exist in:
C:\Users\XXXX\AppData\Roaming\Arduino15\packages\arduino\hardware\avr\1.6.x\platform.txt

However I have found that inside mu PC; C:\Users\XXXX\AppData\Roaming\Arduino15 , there is no folder name packages. I have searched in hidden files also.

3. However I have found platform.txt file in:
C:\Program...

Optimization flags arduino 1.6.5 !