If walking over a stop line with a bike constitutes 'propelling' it across the stop line, then I don't think it's stretching the usual use of language to describe walking a bike down the pavement as leading it on the footpath. But as you say, until there's a decision on the point (which there probably never will be) it's all a matter of opinion. And as, we all know, opinions are like arseholes.
If walking over a stop line with a bike constitutes 'propelling' it across the stop line, then I don't think it's stretching the usual use of language to describe walking a bike down the pavement as leading it on the footpath. But as you say, until there's a decision on the point (which there probably never will be) it's all a matter of opinion. And as, we all know, opinions are like arseholes.