I simply ask for sites they say they have optimized, pull up "SEO Meta in 1 Click" and check basic elements of on-page SEO (URL, Title, H1 - H6 Tags, Alt tags, file names, etc. ) and 99% of the time they fail. Its sad and requires us train people who think they already know what they're doing. Words are less valuable. But if I were to rely on words, I would ask which SEO professionals they follow and what shows and blogs they consume. If they say "Rand Fishkin, Neil Patel or Brian Dean", they would be immediately disqualified.