"Working" Vocabulary

I don't blog about work. But here's a topic that came to my mind because of my job.

I was presenting to an executive and told him we were investigating whether something was feasible. He didn't know the meaning of "feasible."

I remember when I was in grade school, "doable" was not a word. Even now, I expect it's substandard. Yet, in business meetings, "doable" is heard frequently, whereas "feasible" is hardly ever used.

Attention: "Feasible" is a perfectly good word, and it means precisely what people want to say when they use "doable."

Honestly, am I being too pedantic? Or at some stage is it important that those of us who have a larger vocabulary educate others by actually using the words that other people should know, but don't?