Well if crews operating under FAA rules are carrying alternate fuel plus 45 mins reserve then they are already 15 mins better off than under JAR ops rules which specify alternate fuel plus 30 mins.
My company encourages us to avoid adding extra fuel unless there is a good reason and they are correct to do so. They accept however that an occasional tech stop may be required due to unforseen circumstances and would never question a captain's decision to do that. A healthy attitude I believe.