The fact that Lloyd had to ask the FAA, and that the FAA, in their official interpretation, had to add language with qualifiers that aren't in the definition, means that the definition, by itself, isn't clear to the lay aviator.
I've been quite clear that I know what the Lloyd letter states.
The only way I know of Lloyd is because I lurked on this site before I got out of the Army and found a similar discussion. I'd be willing to bet most pilots aren't even aware that the Lloyd interpretation exists. It may not matter at all for someone that's been working for a decade, but for the guys struggling to get their first "real" job, it does.
Coming from an academic background in engineering, I know intuitively and technically that vibration is movement; I know that, at ground idle, the main and tail rotor rotation causes the whole aircraft to vibrate as the CG oscillations cause the airframe to vibrate.
If I were to write the regulation to reflect what I think it ought to be I'd use pretty much the exact same language that the FAA did. I might have to write a letter of interpretation to avbug stating that an aircraft with an APU and hydraulic flight controls doing pre-flight checks doesn't qualify for pilot flight time, and that it would start when the engines are started. Then I might have to change the definition to specify engine power, but that'd be about the only difference. In practice this would result in everyone using oil pressure Hobbs. Except for the glider pilots, of course.
If I were to write the regulation with the FAA's intent in mind, I wouldn't use the word 'move' without the qualifier: away from its parking place. Otherwise I'd use the word taxi. I know pilots that don't log flight time on a helideck, which isn't addressed in Lloyd, though Lloyd seems to indicate that pilot time still accrues during interim landings. I do admit that I don't know if there's a letter of interpretation specifically addressing it. Perhaps someone can enlighten us.
The best definition of pilot flight time is when the aircraft is not attached to the ground. It works for airplanes, helicopters, gliders, balloons, and Icarus.
I don't know why the FAA drew an arbitrary line in the sand that lets airplane guys log flight time when they've got a free hand to finish their coffee, but most helicopter guys don't get to log time until they are in the air. That's probably why a few of us get worked up about it; it just seems unfair, especially since most of us are too poor to fly helicopters for fun so we have to try to get a job doing it. Why would we lobby to change the regulation? The FAA will only change the definition to reflect Lloyd, screwing over all the current and future students and CFIs who log oil pressure Hobbs.
I told my mom I wanted to be a pilot when I grew up. She told me I couldn't do both.