I just picked 2 cities at random Denver to Atlanta March 10 on travelocity fare listing on the right side of their home page.

http://dps1.travelocity.com/lognlogi...ce=TRAVELOCITY

T fare $208 + 20 tax for 2 travelers $456
K fare 498 plus taxes of $20+- for the free ticket=518

Using the T fare you get 2 times as many frequent flyer miles and save $50.00 over the free companion certificate.

I've checked this many times and the results have been the same 95% of the time. (The only exceptions I've found were during certain sales and occasionally in Airtran or Southwest markets) and even then the savings didn't equal the loss of miles.

I would be willing to bet that nobody can point out any market where this is truly a free companion certificate when compared to 2 tickets of the lowest fare and I it would be very rare to find many markets where it could save 5 or 10%.