Your thoughts about cyclists on 70mph dual carriageway?

Round here we have plenty of cyclists who use the 70mph dual carriageways, they have dedicated routes that mostly run parallel to the roads but for various reasons dont use them.

MK we have grid roads systems, so these roads and straight(ish) connected by roundbaouts into a grid pattern and are servixes by dual or single carriageways which are 70/60mph

Then we have 40/30/20 etc in slower more built up areas. However, most of the DC are 70 and there's a lot.

Edit -

To anyone querying the dedicated paths, these run alongside most of the grid roads - checkout the MK redway system. But as mentioned above, there's various reasons they're not using them in assume