

For two and three, even if there weren’t a genetic component, the lifestyle and dietary habits of a family absolutely do impact the next generation of the family. Learned behaviors that increase the risk of alcoholism or heart disease absolutely count as “runs in the family”. Further, “runs in the family” never meant “everyone in the family absolutely has it”.
(None of this directed to the comment I’m replying to, just continuing the thought of the comment.)
They aren’t suggesting using a grease pencil as a better alternative to a graphite pencil, they are saying that the Russian cosmonauts used grease pencils before moving to a pressurized pen.
You don’t need to say “no thanks” to it, no one is suggesting using it. The first comment was ambiguous, but your response to this one is just baffling.