Metaphorical.

1) "This procedure we just took you through will now result in you waiting around for a bit, so rather than sitting around twiddling your thumbs watching the computer think, why not take a break away from your workstation instead?"

2) "This procedure or anecdote we are about to take you through will take a bit of time. Now is a good time to take care of whatever you feel is necessary before we proceed, because interrupting for one reason or another, emergencies barred, would be a not so good thing."

Comes mostly from technical documents, specifically where compiling is involved, as sometimes the process of compiling code takes a while.