I used to be syndicated on an aircraft with a bit of a starting problem (once it started it was always fine). That's where I discovered that on failed starts a Hobbs can jump forward. My record was 0.7hrs without leaving the chocks.
Needless to say, I had to pay by the Hobbs reading, but my personal logbook could only log chock to chock.
G
[ 02 November 2001: Message edited by: Genghis the Engineer ]