Transit, at best, is an *alternative* to driving--it will never relieve congestion [[to wit, I-395 in Northern Virginia, where there is excellent transit service). But because the congested suburban freeway corridors are neither densely-populated nor accessible by foot, transit will never be a viable alternative in these areas.
I disagree...the I-395 corridor's population [[work and residential) is growing and fast, largely due to BRAC. WMATA runs an excellent bus system, even in these areas not directly serviced by rail. These areas [[NoVA) weren't designed to handle the huge influx of residents and development...