Bceause by now it has surely frustrated enough motorists on a daily basis, the term "HOV-4" has made its way into everyday language. But go back to basics--of English as well as traffic-- and you're talking about a regulation that is backfiring. It is the High Occupancy Vehicle/minimum of four riders rule on the newest extension of Interstate 66. On weekdays from 6:30 a.m. to 9 a.m. inbound and 3:30 p.m. to 6:30 p.m. the other way, only this car-and- passenger combination is allowed on the road. The results so far have been fascinating--and bad.

As anyone using the strips at these times knows, not enough people can, or do, qualify. Highway officials argue that three months is not a fair sampling, that carpooling will increase. What has increased so far is the number parking in a new mini-rush jam on the shoulder of I-66 outside the Capital Beltway, where there are no restrictions, to wait for a 9 a.m. run up the ramp. Police have been issuing warnings and tickets to this shoulder crowd, but with little effect.

HOV-4 may have looked good on paper, but not on the road. Clean air and more people to the car are excellent objectives, but so are smaller cars, which don't accommodate four passengers unless two are in the trunk. Some practical adjustments are in order. Why not try HOV-3 for a test? At least this would increase the odds of finding riders and would be more realistic (the police are wise to those inflatable dummies in the back seats). For those Virginians whose daily commute is challenge enough, life in the fast lane could be far better than it is.