As Hybrid Cars Multiply, So Do Carpooling Gripes A surge in the number of hybrid vehicles has left carpool lanes nearly as congested as the regular lanes they are intended to relieve, a Virginia transportation task force said yesterday. A detailed study of carpool lanes on Interstate 95 found that the number of hybrids more than tripled between last spring and October. State transportation officials fear that the trend will continue as more hybrids enter the market and more commuters take advantage of the exemption allowing them to ride alone in such vehicles. The findings reflect the sentiments of carpool-lane...