The cycle lane to hell

It started with me noticing I wasn't far from the top of the leaderboard for number of roads covered in Claygate on Wandrer. Then came the realisation that the only way to top that leaderboard was to ride along some of the A3. A bit of a search of Google Maps showed what appeared to be a cycle lane

So somebody at some point thought it was a sensible idea to ride on the A3 at the Esher junction. And to be fair, it didn't look too bad, other than the laughably narrow cycle lane on the slip road. Although the traffic is fairly fast moving at that point, there's a hard shoulder, which I'm guessing is where cyclists who want to live are meant to ride. But the hard shoulder disappears when the road merges with the Kingston bypass and you can't exit onto that road. You also can't exit at the next junction, by which point the A3 has turned into a nasty, busy, suburban thoroughfare. It's only after passing that junction and avoiding the traffic coming on via the slip road that you can actually exit onto a local road. 

I've searched up and down the road on Street View trying to find the officially sanctioned route for cyclists but I can find no further signs for cyclists. Did they just forget to finish this bit of infrastructure or was the planner actively trying to kill people?

I did figure out a couple of possible ways to escape the A3 before it gets too unpleasant. There's a tunnel under the A3 with a path into Claygate. That does involve negotiating a barbed wire fence but is otherwise OK. 

The two times I've been down that path the tunnel has been flooded so you may not have much luck if you need to get through it.

The other option would be to hop over onto the Kingston bypass via what looks like an unofficial junction drivers have created when they've realised they can't get there via a road. That involves negotiating the cars merging from the Kingston bypass and then probably stopping to get onto the grass, but probably OK if there's not much traffic