Gamasutra, the magazine about creating computer games, interviewed IF author Emily Short. The interview covers a fair amount of ground about creating IF, focusing in large part on Savoir Faire.
GS: What do you think about "pacing" interactive fiction?
ES: The game should stay fun for as long as it takes to play; no aspect should take more of the player's attention than it deserves.
What that means in practical terms will vary a lot from one work to the next. In Savoir-Faire I mostly thought in terms of puzzles and their rewards.