So DUKE is the answer for me: to bypass all the cars around Bukit Antarabangsa. Here is the map which I've colour coded to indicate traffic congestion (the redder, the more traffic), and my alternate route from Melawati to Ampang (in green towards DUKE). Click for glorious technicolour.
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After a few kilometers, the exits are clearly marked: one going North back towards Melawati / Gentings) and the other south towards Jln Ampang. I took the Jln Ampang exit, to rejoin the madness of the congestion.
Merging with the traffic was relatively easy, as I was the rare ones to approach from DUKE. There was only one other car; a white Kancil which tried the new Expressway.
Then it was the usual trudge to get past the corner, for normal traffic again.
Overall, the time taken was about 15 minutes for a journey which took 45 minutes yesterday. So its a real time saver for now.
I did not notice any toll booths, so I can use this route for free indefinitely. The booths are further up the Expressway around the Air Panas / Setapak area. DUKE is not fully complete yet. It currently terminates at Sentul which leads either to the city, or to the new Expressway link (another toll) which feeds traffic to either Batu Caves or Genting Highlands, i.e. meeting MRR2 on the north east.
I am really happy that the DUKE designers didn't do a AKLEH (Ampang - KL Elevated Highway) by not having fully formed interchanges, i.e. only allowing traffic into the highway and not allowing traffic to get off unless they pay the toll charges twice. However I wonder if this would mean that the Mat Rempits or KL Drifters will now use the Jelatek / Ampang section of DUKE to practise.
Try it out, and hopefully there are more people from the area needing to get to Jelatek/Setapak/Sentul/Duta than more people trying to get to Jalan Ampang. Otherwise DUKE will just exaberate the problem.
yk
[Update: 12th Feb 2009: They have started charging for tolls, which is great, because the feed into MRR2 was starting to get jammed in the morning. Yahoo for me.]