Saratoga-
By all means, try the "cocktail" and see if that helps. It did not work for me. After three- count 'em, three- new transmissions, the dealer finally listened to me and replaced the clutch...the car has been perfect ever since, at least as far as being locked out of first and reverse. (Mine was doing it several times a day-very embarassing at stoplights)
A handful of others here have had the problem solved by replacing the clutch. My dealer diagnosed it as an "intermittent clutch failure". (?)
A second symptom to look for to check whether it is indeed the clutch: From now on, when starting your car, leave it in first gear. If, every once in a while, you get a funny little "shudder"...you may even feel the car tugging forward a bit...chances are it is the clutch not disengaging fully. Intermittently, of course.
good luck...if you want, I can supply you with the name and number of my dealer, who has cured two SVTs with the "first-/reverse lockout" this way. Maybe your dealer could give them a call.
Good luck
