I know what the rules say and thats how i log my time, but have had this conversation before. Has anyone ever read an accident report where the helicopter came to some sort of grief while running on the ground, such as someone walking into the tail rotor.(heaven forbid) The report usally refers to the PIC at some stage. The PIC still takes the rap for the accident (whatever the situation may be) but is not logging the flight time, but still has full responsibility for the A/C
And then if you fly an R22 you log the hr meter hrs run off the engine oil pressure, so are logging ground running time as well.
We all know how long it takes some of our fixed wing friends to taxi, run up hold etc, and they can log the lot.
Rules are rules i surpose, but like someone once told me they are for the protection of fools and the guidence of wise men