What are you talking about. Funny how he said release straight after sasuke cast genjutsu on him. If you havent realised thats what most people say after theyve cancelled a genjutsu.He hasn't said that because he only ended izanagi once throughout the whole fight.
It is heavily implied that danzo was comparing their tsukuyomis, why would he compare a regular genjutsu to itachi's tsukuyomi?
Anyway it seems like you have your hands full with debating against these other guys, I'll come back later if it cools down.
Also i believe that danzo was comparing sasuke's and itachi's level of genjutsu in general