Those who are saying "3rd or 4th" over "FA Cup" aren't saying it because they don't want a "day to remember in 2015", they're saying it because they are looking longer term and more pragmatically (IMO).
As some have highlighted, finishing in a CL spot means we'll need to assemble a much deeper and more versatile squad for next season, and we will be able to attract a higher quality of player in the process. And once we have that better squad we'll be also be better placed to challenge for a domestic cup. Win win.
So, no, people advocating a top 4 league place aren't blithely discarding the chance of "a day to remember", they're simply thinking more longer term. 'The Southampton Way' is all about building-blocks. Even if we get knocked out of the CL at the first hurled, we will still have strengthened our foundations as a result of qualifying.
Of course, if we end u doing both the season then everyone's a winner (babe).
Just an alternative opinion of course.
P.s. I actually think we'll fall short of a CL spot in the end but doesn't mean we shouldn't focus on trying to