Spending the equivalent money on policing the roads using the existing laws could have a better effect, it's where I'd prefer efforts were directed.
I'd agree with that. I'm trying to balance campaigning for better policing with for better infrastructure and I suspect many other groups are doing the same. At the moment, the money is going into infrastructure, but the basic design changes are lagging behind, so we're essentially spending a lot of effort trying to stop councils building good-looking badly-designed stuff for a while until the "cycle-proofing" idea helps to fix the Design Manual for Roads and Bridges, and first do the cheaper but more useful infrastructure that is possible (20mph, "except cycles" and so on). Where they won't stop, we're trying to mitigate the worst dangers of either the new bits (Lynnsport Access roads) or what's currently there (the notorious "please wait here while an incoming bus runs you over" bike lane in the Lynn bus station entrance).
I don't know all campaign groups, but I don't think ours is good at predicting which campaigns will win (I didn't expect Norfolk County Council to start removing "motorcycle" barriers at last, for example), so the active campaigns are often determined by which ones cyclists are willing to work on, as long as they're on-message. Our current headline efforts are RoadJustice and space4cycling (which includes 20mph, "except cycles" and more, as well as cycle lanes on major routes) partly because we share them with sister groups like LCC and CTC, and so they take up less of our local resources.
space4cycling is taking up more resources than Road Justice, but that's because the highway authorities are doing more infrastructure stuff and we have to react, else what we will get will be even worse (we've seen this in the past - what Norfolk builds now isn't good but it's less awful) and the police don't seem to be doing so much traffic policing.
LCC is probably different because 1% or whatever of London is a lot more than 1% of any other group's area, and CTC is national, but elsewhere it's as much a do-ocracy as a democracy. If you want to shape cycle campaigns, get involved. You probably won't convince enough campaigners that cycle lanes are never a good option, but if you know the evidence then you can probably encourage restraint where something else would be better.