Yes, that lines up with how I use the vars. On VATSIM, we only simulate two transponder modes: standby and mode C. So I send standby if the “TRANSPONDER STATE:1” simvar is less than 3, otherwise I send mode C.
And if I see a value greater than zero in the “TRANSPONDER IDENT:1” simvar, I trigger an ident. I use my own timer to keep identing for 12 seconds. I only read the value when it changes, so it’s not like another 12 second ident will be triggered if the value is still 1 after my timer expires.