The gravel comment got me thinking about a trip I took that took me through some Colorado mountains. All loaded up, full bags and 2 tour packs. Pulled over one morning high in the mountains to adjust something, put my feet down on the gravel, and fwooomp went the bike over.
Tried a few times to lift it myself, backed into it, did everything I could, but it was just too heavy and the gravel was not my friend. In the end I had to undo all my careful straps and clips and pull both tour packs off before I could get it up. It took me half an hour overall, but I was ready to roll again.
Had to think real hard about what I would do if I couldn't end up lifting it on my own on that gravel, since not one car came by in that half hour.