Opinion time - The Question About Which Font To Use?

I just finished reading Kate Atherley's The Beginner's Guide to Writing Knitting Patterns. In one of the Advice from an Expert boxes this information appeared:

Knitter and Graphic Designer Zabet Groznaya says:
When in doubt about fonts, go conservative. Times New Roman, Arial, and Helvetica maybe boring, but they are clean and easy to read.

This was the advice I used when I first started publishing, partially because it was the most common and made the most sense to me.


A few pages later in the book there's a reference to this source: http://practicaltypography.com/
which says:

"And fi­nally, font choice. The fastest, eas­i­est, and most vis­i­ble im­prove­ment you can make to your ty­pog­ra­phy is to ig­nore the fonts that came free with your com­puter (known as sys­tem fonts) and buy a pro­fes­sional font (like my fonts Eq­uity and Con­course, or oth­ers found in font rec­om­men­da­tions). A pro­fes­sional font gives you the ben­e­fit of a pro­fes­sional de­signer’s skills with­out hav­ing to hire one.
If that’s im­pos­si­ble, you can still make good ty­pog­ra­phy with sys­tem fonts. But choose wisely. And never choose Times New Ro­man or Ar­ial, as those fonts are fa­vored only by the ap­a­thetic and sloppy. Not by ty­pog­ra­phers. Not by you". 

And yes, I've heard this advice many times after I chose the conservative fonts. 

I'm asking because I may update my basic pattern format in the future. Which expert do you agree with? Is the font something most knitters even notice? I consider simple and readable to be the most important factor, but do you?