Hate such logging tips: "Log relevant information in a format that is useable." When I see this, my first reaction is to say "f*ck you too!" :-)
To give it credit, the piece does have some solid logging advice, e.g. "Exclusive filtering [A.C. - aka 'artificial ignorance'] is a god-send to troubleshooting because it’s easier to filter out noise and whittle the logs down to the relevant entries rather than guess at what you want to see." or "Log clients centrally"