Linden,
You raise an interesting point. Whats more effective consistent mailing over a longer period of time. ie 10 mailings over 10 weeks or more mailings over a shorter period of time ie 4 mailings in the first week and keep mailing for a month or so.
I personally will be doing 13 postcards over 13 weeks.
13 over 13 weeks is the best... reason is..
you are still there when everyone has given up or quit..
im starting an 8 x8 8 over 8 weeks this coming year..
if i dont get the result i want..
will be doing the 13 x 13