Pontiac is one side of a new triangular channel system developed by General Motors, complementing Buick and GMC, and GM is pushing to increase the number of dealers that sell all three brands under one roof. Under this structure, most segments are covered between GMC’s trucks and large SUVs to Buick’s premium vehicles and Pontiac’s so-called performance cars, but there’s a big void where entry-level buyers are looking. Company executives believe the Pontiac Vibe, while priced competitively, is too unique to do the job. Therefore, the Pontiac G5 coupe, known as the Pursuit in Canada, will sell for $14,995 including a $615 destination charge when it goes on sale here this fall. The sedan version won’t be tagging along for the border crossing.