Three vs Four training days

There have been some instructors, mainly in the US, who have been teaching 3-day, instead of 4-day trainings. This results in a 21- versus a 27- hour training. It is also supposed to result in more face-to-face practicum time but I am not sure that is happening. Here are some questions surrounding the use of 3-day Basic and Advanced Intensive trainings that the board would like faculty to chime in on.

1. Does a 3-day training lead to more people taking it?
2. Does a 3-day training result in more people going on to practicum, advanced training and certification?
3. Should the person getting 27 hours of training receive the same certificate as the person getting 21 hours?
4. What is shortened or left out of a 21-day training?
5. Should the training price for both be the same?

Please feel free to raise other questions about this topic that you may have.