Rather than relying on the experience of cyclists - naive simpletons one and all - I'll offer a bit of evidence.
The Notional Cycling Strategy (NCS) - agreed policy across public life when it was published a decade and a half ago - looked at various "areas of concern," one of which was Integrating cycling within traffic management practices.
Bearing in mind that the relevant professional body, the Institution of Highways and Transportation was represented on the relevant working group, I'll pluck the following from the document:
4.3.8 Many authorities have tended either to ignore cyclists or treat them as marginal users of the roads. Education and promotion are important in overcoming attitudinal and institutional barriers.....
4.4.7 Professional bodies and academic institutions need to raise awareness of the relevance of cycling and improve practical skills. Cycling issues should be integrated into mainstream engineering, planning and design training, including National Vocational Qualifications (NVQs), not taught as separate topics. There should be a programme of training for existing professionals, particularly local authority consultants.
The NCS was pretty much killed off, of course, and that was in no small part the responsibility of highwaymen who wanted nothing to do with it. Moving into the modern era, the subject of the training of highwaymen came up earlier in the year in the All-Party Cycling Charade. I'm grateful to TonyR for this post from which I've quoted part:
TonyR wrote:During the recent Parliamentary All Party Cycling Group enquiry a Regional Director of the Highways Agency admitted " As a highways engineer myself I spend an awful lot of time designing roundabouts and bridges, actually I didn’t spend a great deal of time at university or subsequently looking at provision for non-motorised users.”...(My emphasis)
I'm keeping an open mind, but on that evidence, things haven't changed. IMO: It ill behoves anybody in that line of business to sneer at what they see as the shortcomings of cycle campaigners. A large part of the problem lies with them.