What's really the proper dimensions for the Publication logo?

Hi there,

Within Ghost Admin, under the “General” settings, I’m being told that the Publication Logo should be

at least 600px x 72px

Per Google documentation

The logo should fit in a 60x600px rectangle, and either be exactly 60px high (preferred), or exactly 600px wide

Question: what dimensions do you think I should use, what would you recommend?

And out of curiosity, where do you think the 600px x 72px comes from?

Thinking to myself: it would perhaps be a neat solution to have a separate AMP logo upload, but sure that would complicate things, both for the developers of Ghost I guess, and the common user. Also, I see masses of publishers having all sorts of publication logos in all kinds of sizes and shapes, and it seems to work fine with most themes?