Originally Posted by
MDtR-Chicago
Shame on me for not citing my source, because I had some basis for my comment.
Looking at
udustats.com, here are the stats for this route:
2P: BOS-ORD 44%
2P: ORD-BOS 36%
[...]
(There aren't many data points for 2P so it may not be statistically significant... but it's around what I would intuitively expect.)
Those are not the correct numbers. For one thing, you appear not to have selected UDU, as the numbers above are nominally for
all upgrade types. (BOS-ORD is 38% if you add that filter. I don't think the OP is going to be using SWUs.) For another, ORD-BOS -- all types -- is actually at 40%, since one of the few data points is a duplicate.
I looked at udustats before posting, too. Unsurprisingly, the numbers bear out my point about the 752s:
2P BOS-ORD UDU: 75% (small sample size of 4, admittedly)
2P ORD-BOS UDU: 60% (3/5, with duplicate thrown out)
If the OP has absolutely no discretion in which flight/schedule to book, then yes, the odds of an upgrade are fairly low (meaning 1/3 of the time, which I would not consider "almost never").
If, OTOH, the OP has some freedom in choosing flights & can cherry-pick 752s, that will substantially improve the odds, likely to well above 50%.