I duplicated the lowest p-state too. Yes, first i set it to 700 and got a KP, but at 1100 works fine, except for the big gap (12x-22x).
You should be using 1100. Only MacBookAir5,1 and MacBookAir5,2 use 800 MHz.
Take a look at the attached SSDTs, those give me all the p-states from 8, 12, 16...33). You will figure out the difference much faster then me it might help you at further script development.
The first problem I want to solve is the duplicated P-State, but that won't happen when people have EIST enabled in their UEFI BIOS, OC and use values that even Apple isn't using.
Listen. I am fine about using 800 MHz, but only when Intel said that it can be done. That Intel supports lower frequencies on desktop processors, and that using it won't hurt the lifespan. Better safe than sorry.
Also. The 2012 iMac's aren't using anything below 1600 MHz. The 2012 Mac mini and MacBook Pro don't use anything below 1200 MHz. Only the MacBook Air uses 800 MHz.
I am using RevoBoot. The only boot loader I'm aware of to disable EIST. As it should, otherwise Intel's SpeedStep is doing the hard work. Not Apple's CPU PM, which is what we want. Don't we?