The notes in runes and builds pretty much explain the playstyle. However, I will add a comprehensive guide soon.

Update: Nevermind people, it does not work. You can never carry as a support when your Katarina manages to die 11 times in 14 minutes. The build itself is strong and you can easily 1v2 the bot lane, and with a decent adc, you may even 2v3 and both live. However, that won't stop the 19/1/3 Fizz that is heading your way. Most champs that you will not play against that get fed are usually mobile ones and Cho'Gath cannot deal with them very efficiently. So, just play top or mid as you are not braindead and at most will die 3 times in 15 minutes with your insane sustain. Their bot may now be the ones that have 15 kills in 10 minutes but you can still one shot the adc so it does not matter.