Those on the City Council who are toying with the idea of a bus-based transit system operating partly on a raised guideway owe the public clear thinking on transit.

First, they will have to listen intently to what Mayor Mufi Hannemann's proposed panel of experts might say about the Phileas Advanced Public Transport System. That blueprint has vehicles on an elevated busway and then branching off at street level.

The problem, as city officials note, is that it does not meet federally approved guidelines and would require the city to go back and redo key planning documents. Its carrying capacity and speed fall short of the mark.

The mayor has countered that the Dutch system wouldn't fit as neatly into the network of "transit-oriented development" centers to be built at major stops, complexes to help pay for the project.

But key council members — including Councilwoman Ann Kobayashi — aren't buying that argument. The only real difference with the Dutch system, she said, is that tracks won't be required, potentially saving on the cost of insulation along the guideway.

It's hard to believe that it's that simple. There are good reasons experts should reject the busway approach. For one: A bus network based in part on diesel propulsion is not the best hope of reducing Honolulu's dependence on conventional energy sources. Ramps leading on and off the guideway will also be a visual blight.

But the biggest problem is that choosing this technology will force a do-over of planning documents, which could add needless delays and endanger the city's standing for federal funds. An about-face like this would not communicate the city's commitment or vision and may ultimately sacrifice the security of federal funding without a payoff.

The council is willing to hear out the experts — or at least go through the motions.

"We'll listen to all that," Kobayashi said, "but they have to tell us the truth, and the council will decide."

That decision had better be based on something more than a political turf battle, which is what it looks like now.