Originally Posted by
redtailshark
Never mind $1000s of more for a DL M-class fare than CO wants for actual Z business class fares. Astonishing!
Actually it was $1000, not
$1000s which would mean
thousands (plural).
If I've asked you once, I've asked you a million times - please don't exaggerate! 
OP said October, so I randomly picked the 13th and the 20th and looked.
Lowest Biz class fare on those dates at continental.com is $3626 with taxes and fees. That is a Z fare. I looked at the restrictions (f
or which I had to enter the values of one of those text images to even get to see it. How weird is that???) That's a non-refundable ticket with $400 change fee.
Delta's M fare on those dates is $3016 with taxes and fees. Non-refundable with $250 change fee.
Perhaps the OP was using different dates, and of course I am way to lazy to bother to see if upgrade inventory is available.
Anyway, doing my famous :-:
BEST IN CLASS :-: math, $3626 minus $3016 is (drum roll please) Delta's M $610 cheaper than Continental's Z fare.
Astounding!
Changing the Delta search to bring up I fares resulted in a total of $3838.80, non-refundable with $400 change fee. So in that case it costs $212 plus change to fly the unfriendly skies in paid business class.
David