In response to some of the above from an instructors point of view;
Inclusivity; The scheme I work for provide bikes if required, depending on the area this can equate to anything between 10% and 80% of the kids needing to borrow one. Non riders sessions are held in the playground for the ones whose bike handling isn't up to them coming out on the road or who have just never ridden a bike before.
Helmets; My scheme insists on helmets (instructors included) and has loan helmets available, helmet checks and fitting is covered before they touch a bike. When I say 'what keeps us safe on our bikes' 90% of kids will say 'helmets!' At which point I put them right and explain the limitations of cycle helmets. If it was up to me I wouldn't insist and wouldn't wear one, but I think most schools and parents expect it and it's not really a problem.
Telling them to ride on the pavement; I make it clear that they shouldn't be on the pavement unless they're pushing their bike to avoid riding a particularly hazardous section.
Attitude of some motorists; Yes, it absolutely stinks, Bikeabilty teaches pretty assertive riding (riding in secondary, door and a bit more, owning your space at junctions etc.) Obviously, expecting most 10 year olds to put it into practice when on there own is probably asking too much, but you can only hope that some of it will stick as they get older and that they might even remember it when they get behind the wheel of a car in a few years (or maybe explain to their WVM dad why that cyclist is 'holding him up').
So, whilst Bikeabilty isn't the answer to all the problems cyclists face on the road and the way it is delivered can be less than ideal it's definitely a step in the right direction IMO.
Of course, if I didn't think that I wouldn't be doing it!