Or perhaps some more positive phrasings:

- If you know this much about memory, you'll know more than 99% of programmers.

- What 99% of programmers don't know about memory.

This is what people says when they have a dataset of 100 entries(<100mb) on their developpment laptop. How funny they look when production guys show them how their lame piece of code doesn't scale up with billion of entries in the production platform...But they dont care cause they are developpers, (or so called). Until the production guy rewrite their code and have them fired for incompetence (true story).