I'd put it more directly. Anyone wanting to log taxying time to the runway and back without having flown must be an utter ar$e.
I taxyed a Vulcan a couple of years ago and yes, put it in my logbook because it was rare and interesting - and it was exactly 25 years since I'd last taxyed one. But as for logging the time? No!
I also have the following in my logbook:
29 Sep 1991 Fury ISS N36SF Southampton Docks (0545Z) - Southampton Airport (0710Z). Remarks: Road tow, av. GS 3.9 Kts.
But it's on a photo stuck to the page!
Should I have logged the taxying time for all the Hunter compass swings I did in 1976? I think not!