I always logged 15 minutes on duty when I arrived, and 15 minutes when I left.... Never got hit with any log violations, and always received detention pay. The rest of the time spent at shipper or receiver was usually logged in sleeper.
I always logged off duty with the note wait when I first got there. Some customers would take their sweet time checking you in and I didn't want to log any more than 15 minutes on duty. When they put me in a door or told me where to drop is when I started my on duty. Otherwise I was either off duty or in the sleeper. They have audited my e-logs twice without any problems or violations.
I have totally revamped my logging. I used to do what you said, waited to show on duty until I got checked in and told what to do. but I changed it now, as soon as the truck hits the gate, its on duty, then after checking in and docking it, I go off duty with a note, "released from duty by ...-shpr or cons- " then when they tell me I am done or the green light comes on, I hit the on duty again, and finish it all out. all in all, it maybe adds like another 15 - 20 mins, not really all that much time to my on duty status.
and its the same thing if I can pull straight into a fuel island if I am lucky and don't have to wait, hit the on duty then fuel then off duty.
I will admit, I was a bit low on logging any time on line 4, like for me, its amazing how you can fuel the truck in less than a minute, lol.