Yes cyclists in the main have to share the same network. And that network in many places is just overburdened. My fastest route to town is down a country road that has the national speed limit. Local drivers complain about cyclists even using this road - because it 'slows' them down. Anyway the road has become hellish, and I've witnessed enough after/accidents to just bypass the road these days for an inferior, but safer dirt track. The irony of course is that that very same dirt track could make for a very good cycle lane. Build them and they will come. The pedestrians/country side ramblers won't be too impressed mind.