Al,
We towed a Honda Accord for 10 years and went through the procedure, probably was less than 10 minutes, abbreviated a bit to more like 6-7 minutes. The sequence is important and pausing in each gear. Never going from reverse to neutral as the last step is critical, always drive to neutral. If we were traveling longer then 6 hours, we would when we took a rest stop break, go through a 2-3 minute gear pass through at a point that hour and travel wise was convenient for us.
From my experience there is some leeway and the times they call for are sure to be more than adequate. Some abbreviation worked for me without any transmission issues over 10 years.
Later Ed