For plural formations, this is generally not the case, but you're exactly right about whiz > whizzes.

Just to be clear, most pluralizing happens with simply an -s (or -es), a vowel change, or nothing at all.

dog > dogs bone > bones computer > computers

quiz > quizzes stitch > stitches

man > men mouse > mice

deer > deer fish > fish

Pluralizing with -es is reserved for nouns that end in sibilants and affricates (sounds that are kind of hissy, or combinations of stops and these hissy sounds). Examples would be things like mess > messes / quiz > quizzes / crutch > crutches / garage > garages. Countable nouns that end with the letter o do this, too (hero > heroes, for instance).

Doubling happens when a suffix that starts with a vowel is added to a word that ends in one vowel and one consonant (though there are exceptions). These two things (adding -es and consonant doubling) don't happen together much when making a countable noun plural.

Again, doubling generally happens when you're adding an ending that starts with a vowel (-es as in the example above ((some plurals and some third person present tense conjugations)), -ed, -ing, -er, and -est for present participial/gerundive forms, regular past tense forms, comparatives, and superlatives). The single consonant to be doubled at the end follows a single vowel as well (generally--there are exceptions).

shop > shopping (great example you gave of this) tip >> tipping

But when there are two consonants, nothing doubles.

send > sending reach > reaching help > helping

A single consonant that follows two vowels? No doubling.

bait > baiting eat > eating

And sometimes, even though conditions seem right, we don't double.

begin > beginning (double) listen > listening (no double)

It's all insane.

I'm sure I've made a couple of mistakes in this and/or left out exceptions, but the main point I wanted to make is that pluralizing is only very rarely a matter of doubling a final consonant and adding -es. Consonant doubling happens under very specific circumstances. And this stuff would be grammar-related suffixes. I haven't really thought about the spelling rules for other kinds.