Everyone wants Radical Inquisitors to be available, but is this even possible with the new state of affairs in the Inquisition codex. According to the ally charts no. You cannot ally with Chaos armies.
So up comes the question..... Since you can ally with an army like the Imperial Guard, can you take the Imperial Guard as your primary detachment, Chaos Space Marines as your ally (allies of Convenience), and then take an Inquisition detachment since they are allied with the Imperial Guard?
I am going to assume no, but of course I have been asked this a couple times already. So page 72 of the codex is where the information can be found, that discusses how allied forces treat other allied forces.
Whats your take? It would be wonderful if there was a way.