Like its musical comedy predecessors at the Princess Theatre, "Oh, My Dear!" is tastefully costumed, daintily mounted, and calculated to appeal to a large percentage of the public which made the previous O-perettas so popular.
The basis of its comedy, aside from an occasional well-turned phrase, is the familiar theory that there is nothing so funny as a married man, unless it be two of them. It was to preserve domestic peace that the proprietor of a health resort was obliged to introduce the impeccable Joseph Santley as a young man with a Broadway reputation—not altogether a new situation— and it was to sustain that falsehood that a number of others had to be evolved. And so grew the plot, embellished from time to time with such musical-comedy observations as "Husbands are like dollar watches— you're darned lucky to get them guaranteed for one year."〔Music Trades: Volume 56 – John C French editor, December 5, 1918, Pg. 80〕

During twenty-five years of theatergoing one learns that there are two kinds of musical comedies—the "low-brow" sort, and those in which the girls aren't seen for ten minutes after the curtain rises. The exclamatory school presented at the Princess runs to cleverness rather than to comeliness, but the cleverest of librettists, lyric-writers and composers grow weary and a trifle stale, and so it happens that "Oh, My Dear!" lacks some of the freshness and sparkle of "Oh, Boy!" and "Oh, Lady! Lady!!"
Guy Bolton's book is rather more frankly than usual of the scrap variety; P. G. Wodehouse's rhymes are not so startlingly felicitous; and Louis A. Hirsch's music, though pleasant to take, has a somewhat familiar flavor.
The story concerns the stock mild-and middle - aged married man who hasn't kicked over the traces since he sneaked off "to a Burton Holmes Travelogue in 1916," and who gets himself into the stock complications by inducing someone to pass himself off as someone he isn't.
Then the wife of the someone he isn't turns up, and we come to the stock situation in which a man and a woman who have been but casually acquainted are assigned to occupy the same chamber.
This tangle is unraveled by a company including Frederic Graham, Roy Atwell, Joseph Allen, Ivy Sawyer, Joseph Santley, Georgia Caine and Juliette Day. "I Wonder Whether," "Our City of Dreams" and "You Never Know" are the best of the song numbers.
In comparison, "Oh, My Dear!" suffers chiefly by being set beside its predecessors at the Princess—it is announced as "the sixth annual New York Princess Theater musical comedy production."〔Green Book Magazine, vol. 32 #1, January, 1919 pg. 178-179〕