I think the most obvious argument somewhat rubbishing this study, other than biased funding, is the revenue lost from people NOT driving and switching to bikes instead. Petrol, cars, MOT’s, tax, speeding fines, Insurance companies, car hire and the millions employed in car related jobs far outweigh the relatively meager £3 billion ‘gained’. Do we really have to lie to people about the benefits of bikes? There are so many valid reasons to use them.
I doubt many people have actually got rid of their cars, so MOTs, insurance and tax are probably pretty much the same, as are the millions (really? 1 in 60-odd people?) employed in car related jobs. Don’t see why you’d expect it to affect people hiring cars either.
Petrol maybe, but if it’s enough to be significant then there’d be a correspondingly lower cost in congestion and accidents to offset it a bit.
Dunno where speeding fines go.