I'm not sure I understand the logic behind not allowing activities to
trigger workflow rules.

I would like to do a couple of things that the designers of the product
apparently felt I shouldn't be able to do:

1. Create appointment activities in a workflow rule
2. Create other activities as a result of an (appointment) activity status
change. Specifically:
a) Automatically send a templated "appointment reminder" email before
the appt.
b) Automatically send a "thank-you" email after the appt.

Does anyone know how these might be accomplished?

Thanks!