He doesn't have to though. No, it's not ridiculous.

Seen that one, bad advice. I always prime. 

Congratulations that you always prime. Here's the thing……

It's not bad advice for not using primer. It's a matter of choice, not a set rule that you "ALWAYS MUST" prime. It's a matter of choice, not a hard general set rule.

I know a lot of guys that never prime their kits. I rarely prime but the only exception I will prime is when I'm using Mission Models acrylics. Why? They scratch easily on unprimed surfaces.