Nice tips for newbies, and even pros sometimes forget those tips.
That's a must for the newbie tips. I remember I even sent someone some bitcoins with almost no fee back in 2013 and it never confirmed.
This article have missed to cover about low fee newbies used to put to save cost on payments leading unconfirmed transaction for many hours. That will make them panic about bitcoin and they will start blaming bitcoin network for it and some may even opt out from the idea of using bitcoin again. 
That's a must for the newbie tips. I remember I even sent someone some bitcoins with almost no fee back in 2013 and it never confirmed.