What I'd like to know though is if there is any way to install .79 stock leak on the safe side as well. Why?
Because I can leave the non-safe side untouched and then play with nands in the safe side (install custom roms on top on .79 on the safe side - eg simplex).
Is that possible?
Thanks guys.
Partially correct. Here's how safestrap works from the first install.
You install the apk and the recovery, you boot into the recovery.
You enable safe system, as soon as you do this, safestrap makes sort of a nand backup for the original system. You can then format /system, wipe data/factory reset, wipe cache, wipe dalvik, flash a custom ROM.
When you disable safe system, it makes a sort of nand backup for whichever custom ROM you flashed on the safe system.