If the Virginia General Assembly makes good on its threat to ratify a 65-mph speed limit on rural highways, I will miss the privilege of using I-66 west of Fairfax.

Do the legislators ever travel these roads? Do they realize that motorists in 1988 regard a posted speed limit as a minimum velocity and that obedience to that speed limit is practically an invitation to be rear-ended, sideswiped and run off the road?

I do not like driving. I do not like speed. I do not feel safe driving my Chevette at speeds over 55 mph when I can pedal it that fast. Every time I use Rte. 66, even within the Beltway -- and this happens only when I absolutely cannot avoid it -- I finish the trip feeling as if I have just survived a demolition derby, nearly unhinged by the constant looming of speeding vehicles in my rear-view mirror and by the furious refusal of drivers in the exit lane to slow down enough so that I can make a necessary lane change without driving at 65 or faster.

Maybe a good driver -- one with lots of experience and exceptional vision and coordination -- can handle a car on an interstate at the speeds that will surely become common if the 65-mph limit is passed. I do not have this skill, and I doubt that many others do. I can only hope that if the limit passes against all the arguments of humanity and common sense all but superlative drivers will have the sense to be terrified off the roads.

KAREN E. MURRAY

Arlington