IMHO it does look like back to back ticketing. The classic example of back to back ticketing I've heard of is a business traveller going to the same location two weeks in a row (as I am doing). So for example, I'm doing these trips soon:
(W1= Week 1, W2 = Week 2)

Ticket 1: W1-Sun X-Y W1-Fri Y-X
Ticket 2: W2-Sun X-Y W2-Fri Y-X

Both are very expensive fares since there is no Saturday stay. I could do this:

Ticket 1: W1-Sun X-Y W2-Fri Y-X
Ticket 2: W1-Fri Y-X W2-Sun X-Y

This would be considerably cheaper since both flights have a Saturday night stay. Basically I switched around my point of origin to get the cheapest fare and flew right back to my 'real' home to get the cheapest fare.

Hence, this is similar to what you are doing and I do believe is back-to-back by airline rules. I personally wouldn't risk it, but your mileage may vary (literally )..

Good luck either way you go.

BTW I believe this may actually be nested tickting than back to back ticketing -- both not allowed by airline rules. Whatever it is called it's frowned on by the airlines. They might cancel your second ticket, or not give you the miles, or worse charge you the difference in cost of two full fare tickets.



[This message has been edited by dg1 (edited 10-20-1999).]