Well, since there are so many bad but little used tunes (and also excluding contemporary-genre "tunes" to make this not like shooting fish in a barrel), I'd focus on traditional tunes that are commonly esteemed among many sacred musicians in the Anglosphere. (How's that for redefining a question? Sorry.)

What comes to mind are tunes that organists seems to love but that are more tiresome for singers (which seem to be a speciality of English organists of the 20th century*, and those who ape them), such as:

1. Vaughan Williams: Hail Thee Festival Day. (It's this that gave my idea for the mash-up tune: SALVE FESTA DIES IRAE.)
2. Festival Canticle (sucks all the joy out of Easter like a giant vacuum)
3. ABBOT'S LEIGH (an organ solo cum vocalise)

* Postscript: a related group of tunes are those that are deadly when handled too stolidly (which will be the temptation of many organists) but that can work if sung to the right text in a more flowing tempo and with a lyrical touch: one example that comes to mind is THE KING'S MAJESTY. (I love DANBY, but would hate to hear it under the wrong hands and feet.)

I don’t like ABBOT’S LEIGH, and I had a particularly difficult encounter with ORA ET LABORA.

Salieri.

1. Yep.
2. Yep. Yep.
3. Do you mean? STELLA!!!!!!! http://www.hymnary.org/text/hail_queen_of_heaven_the_ocean_star

I like all three of Liam's choices. Oh, well, it takes all temperaments!

1. SAINT CATHERINE
2. GENEVA
3. VESPER HYMN
4. PURPOSE
5. MUELLER
6. OLIVET
7. AUSTRIA (which is a perfectly good tune, but even if the text says "Glorious things of thee are spoken" I'm still thinking "Deutschland, Deutschland ueber alles".)

The generation for whom AUSTRIA had those connotations in real-time is passing away, and it's not been an issue in my experience the way it was, say, in the 1970s. Haydn knew how to write.

I forgot another one I detest: ODE TO JOY in its form where the absolutely idiotic practice of squaring up the last line is used. The genius of the thing rests on the anticipated rhythm of the last line. Either do it right, or use AUSTRIA instead (Joyful Joyful We Adore Thee scans beautifully to AUSTRIA - Ted Marier set it, on facing pages, to both tunes, including the correct version of ODE TO JOY).

https://en.wikipedia.org/wiki/Gott_erhalte_Franz_den_Kaiser

https://www.youtube.com/watch?v=yqWQbK2xncA

The generation for whom AUSTRIA had those connotations in real-time is passing away

Let's hope so. As always, the Society holds out.

I happened to be reading a newspaper editorial written by an SSPX supporter who was extolling the virtues of the Old Mass. He described how it brought tears to his eyes hearing Tantum Ergo sung to the tune above: "Part of this magnificent hymn contains the Tantum Ergo, which may be sung to the glorious tune of “God Save the Kaiser,” the greatest national anthem ever composed, the divinely-inspired [sic] work of Franz Josef Haydn, that most Catholic of composers from that most Catholic of countries, Austria..."

The Francophile and Anglophile inside of me ceased their eternal feud for just a moment to issue a collective gag.

Stimson

You saw Anglophilia in the mirror, just in lederhosen, that's why.

Liam, I admit my ignorance as to your meaning. I mean the extra eight notes in the last line, which is then repeated unneccessarily.

ENGELBERG
EBENEZAR
NON DIGNUS
(BOOM!) mic drop

Matthew

Yes. The eighth notes are canonical in much US Catholic congregational practice. Written music to the contrary is moot.

@Adam Wood CAN YOU EVER CONTAIN YOURSELF? Any harmonization which is not Vaughan Williams' harm for Iste Confessor.

Amazing Grace
Brother James' Air

By the way, in case anyone hasn't heard the story, and since both these hymn tunes have been mentioned above: they are related.

ABBOTS LEIGH was composed by one of the BBC's producers of religious programming in 1941 so that their Sunday services broadcast on the radio would have a tune to replace AUSTRIA, which had fallen out of fashion.

I think I like or love every single hymn mentioned in this thread so far.

You also like Enya.

And Sweelinck.

So....maybe you have bad taste, is all.

You still like Enya.

Sweelinck is a nefarious foe.

What about the three I mentioned?

Somewhere in the TV Mass archive on YouTube there's a TV Mass where that common friend of ours whom you cooked hot dogs for a few months after you cooked hot dogs for me just brutalizes DUKE STREET while subbing for me. We've now started using it as a verb - "wow, you really DUKE STREET'd that..."

I'm not sure I've ever seen such a disconnect between what professional church musicians like and what people enjoy singing.

So much so that I'm surprised no one has mentioned NETTLETON.

Kathy

I will grant you that my bias against the squared-off ODE TO JOY is definitely not an issue of popularity but a purely musical in nature. However, my original three nominations are more of an example of things organists love but American Catholic congregants much less so....

I find the standard harmonization for ADESTE FIDELIS to be both really boring and extremely difficult to play. I really need someone to write a new one. With jazzy chords. But easy to play. Like three voices, tops.

You could always do as the "contemporary" group at a local parish did for a Christmas Eve mass. They sang "Joy to the World," Three Dog Night, as a recessional. BTW, the members of that group are about as contemporary as rust on the Titanic.

I tend to like most things traditional, unless the harmonizations have been butchered by Richard Proulx. What I don't like are the "hymns" written in the seventies by supposed Catholics, and heretics of various persuasions. I may be tired of the older hymns, but they are generally far better than what has been written since.

...no one has mentioned..

Ha!
That's because it isn't worth mentioning.

I'm kind of surprised no one went TWO OAKS yet.

KREMSER loses me within the the first four bars, and FINLANDIA doesn't work outside its symphonic origins. I will admit to quite liking NETTLETON and ABBOT'S LEIGH.

My objection to RUSSIA and AUSTRIA isn't that they aren't good tunes (they are), but that they're already well established as national anthems (Germany still uses the same tune, beginning "Einigkeit und Recht und Freiheit"), and feel a little like singing a sacred contrafactum of La Marseillaise (or The Star-Spangled Banner, for that matter.) Too weird.

How about LUX EOI and SAINT KEVIN? I love Sullivan's operettas, but he really tanks as a church composer.

Also BROTHER JAMES'S AIR.