How to create congestion

New traffic island on A105 Green Lanes towards the top of the hill alongside Finsbury Park, just before Manor House tube station. Big wide bit of road now reduced to one lane - I suppose to protect the juction with the side road, people are aways being let out by queuing cars and being hit by something going the other way. Result? The queue for the lights now stretches all the way down the hill and under the railway bridge into into Haringey. Brilliant!