Where's the verb? A question of style?

Where's the verb in the highlight part? Is it ungrammatical or a question of style? If it's the latter, when should we imitate it?

Sentence:

Yes, this approach employs the best analytical tools that economics can offer, but it also allows us to follow whatever freakish curiosities may occur to us. Thus our invented field of study: Freakonomics.

Thanks in advance!

It's a style.

I'd advise against copying this style until you are really comfortable with standard writing. Part of being an entertaining writer is knowing when it's okay to break the rules, but you have to really, really understand what the rules are first.

Grammar Geek wrote:

It's a style. I'd advise against copying this style until you are really comfortable with standard writing.

I get it now. Thank you Barbara!