I disagree with him about letting the police search your vehicle if you hid your stash 'properly' (the way he teaches).
Refusing consent to search is not an admission of guilt. He say, correctly, that many cops may take it that way, but the law and the courts are on your side. Let them bring the dogs if they think there is enough reasonable suspicion.
The best thing you can do if pulled over and you have something on you is keep your mouth shut. The more you talk, the more likely it is that they will get their reasonable suspicion, which isn't enough for a warrant, but enough to let the dogs sniff around the outside of your car.
Try to videotape (camera phone should be sufficient) so your attorney can if they get the dog to false alert.