"How long did it take you to learn this new thing?"

Paradigmatic career-making ideas and papers are rare and take years or decades to produce. But academia doesn't run on that coin - just regular papers and small ideas.

Is it too much to suggest that 1 every few months is possible for someone who ought to be a professional rationalist, who reads the literature carefully and thinks through all their ideas, who keeps a pad & pen handy to jot down random notes, who listens to the occasional off-kilter but insightful student questions, and so on?

That is 4 ideas a year, and over a graduate student's 4-year term, 16 possible papers. Not counting any prevarication.