Just as on off handed Suggestion, might it be possible to have a command to idle?
Once typed, the character would be free from godly punishment (for idleing, anyhow), but would gain no lesson credits.
Seem to be no more complicated that turning off lessons for the person, and no more harmful to the reality of the environment than, say, the timeout command.
Just a thought...
Written by my hand on the 10th of Midsummer, in the year 1008.