You're lobbying for road construction over parkland; you misrepresent the facts to make your case.
You don't like the description that attaches to that kind of politicking?
Cry me a river, road warrior!
Misrepresent the facts? I said I thought it was half tarmac, the area to be lost, which was my subjective impression from walking through there and seeing the line that was painted on the ground a while back. Crispy's figures showed that in fact it's about a third tarmac. I apologise if my guess was a little out.
If we want to be picky I could find the bit where you said the new slip road would be "wider" than the existing one when in fact, from the information to hand, it will actually be narrower. It will also be raised to pavement level which is a well practised strategy for slowing down traffic.
I think the problem here is that people are descending into a fit of rage because they can't see past the fact that x square metres of the park will be "lost". That's such a stupidly simplistic way to look at what is a reorganisation of the whole layout of that bit of Herne Hill.
I am interested in the quality of public space, not quibbles over square metres. If you look at the image below, I have coloured in red the areas that are currently public space accessible to pedestrians but which will become roadway, and I have coloured in green the areas which are currently roadway but which will become public space accessible to pedestrians. If you subtract the amount of green from the amount of red, there really isn't such a huge area that has been lost, is there?
In return for that very small area being "lost", we get extra space for bus stops and a vastly superior approach to the park. At the moment, starting from the corner with the road to the station, you have to firstly cross several lanes of traffic with just a small pedestrian island in the middle. You then have to cross the existing slip road, which always feels a bit dicey because it is sharply curved and you can't see very far along it to see if cars are coming (and vice versa; they can't see you). Once you have negotiated that slip-road, you are then squashed onto an unsuitably narrow pavement, in between road barriers and the park gates.
In the proposed scheme, the same journey involves crossing three lanes of one-way traffic to a generous pedestrian island that unlike the existing ones has space for more than about four people. Then, across another couple of lanes of one-way traffic onto a large paved area with trees (having looked at aerial shots it looks like these are retained trees currently in the winos' corner). Then across the new sliproad which as previously mentioned is level with the pavements and has clear sightlines meaning cars can see pedestrians and vice versa. And then you are into the park.
This is not even mentioning the associated improvements that will see the whole of the station approach road pedestrianised.
So for me it's not a difficult decision. Either be dogmatic and simplistic about never in any circumstances losing a bit of parkland, or look rationally at the benefits gained in return - look at square metres of public space rather than park space, and look at quality rather than quantity. I choose the rational and sensible approach.
Which apparently makes me a "road warrior".