How submerged does a reference have to be before it drowns?

“What you end up remembering isn't always the same as what you have witnessed.”

“We live with such easy assumptions, don't we? For instance, that memory equals …”

“When we're onstage we're not literature, we're sitcom. You have to have catchph…”

“When you are in your twenties, even if you're confused and uncertain about your…”