A few months ago, I struggled mightily with a brilliant Matt Gaffney metapuzzle, where he employed the doubling trick to devious effect. It was such an amazing fist-pumping moment when I finally figured it out — and then realized that he managed to place the theme entries at 11-, 22-, 33-, 44-, and 55-Across!

Today's puzzle works, but you can imagine how it's a let-down for me, considering the aforementioned puzzle. I like that Joe included so many of them … eight, is that right? I had a hard time keeping track, since these shorties kept getting lost in the shuffle. I also appreciated that Joe (mostly) kept to ones where the meaning completely changed once doubled. SING vs. SING SING is a stark difference, for example.
Hmm … SING vs. SING SING vs. SING SING SING. Crossword theme radar activated!
Gridding around eight short entries — plus a central themer — can be problematic. Wait! What's the big deal, you ask, since all the themers are only four letters? I'm glad you asked! Crosswords have to be 78 words or less, so …
Huh? Why 78? Because if there are more than that, it's difficult to include any long, interesting entries.
What, another question? Why does there need to be long, interesting entries, you ask? Because a bunch of shorties heaped together makes for a dull solving experience.
But Jeff, why—
Because REASONS. Harrumph.
Long story short, themers are usually your long, colorful entries, so you can fill around them with shorties. When your themers are those shorties — and you have to place them symmetrically — getting flavorful long or even medium entries is tough. GLOOPS, A DAY AGO, BALIN, PLATEN.
I understand Will Shortz's rationale for not getting into the meta craze — some solvers hate the frustration that these can bring — but it'd be great if the NYT actively sought out more original ways of presenting ideas.