This is an equal opportunity forum where everyone has an opportunity to make a positive contribution. Any time you think you can do a better job than I have, you are welcome to try. I will watch from the sidelines and applaud your efforts. It stands to reason that in order to check the flow of air through a series of valves, there must be a source of air of sufficient volume and pressure. I would think that the appropriate source would be the Thermactor Air pump AKA, smog pump. If that principle escaped you, there is very little I can do about that. Please note that in order to have vacuum present, the engine must be running or you have connected an external vacuum source. Since most of don’t have a vacuum pump capable of delivering a constant 16”-20” of vacuum, the running engine is the vacuum source of choice. The tests are arranged in order so that the first item tested must be functional before you proceed the next test item. You also made an incorrect assumption that testing the vacuum control TAB & TAD solenoids was accomplished by observing the air flow through the control valves. That is not the case. The control valves are tested first by the application of vacuum to them individually and observing the airflow switch from one path to the other. The vacuum control TAB & TAD solenoids are tested by the application of a ground to the proper wire. At the time the ground is supplied, you should be checking for the absence or presence of vacuum at the solenoid valve’s output port that connects to the control valve. You can use a vacuum gauge or feel the suction on your finger as you cover and uncover the output port on the valve. If the logic of all this escapes you, there is very little I can do to help you.