As depicted in this example, that choice only changes the shading of the calendar background for the specified timeframe.
It will not hide the excluded times from being displayed.
I agree. Very annoying having to see those "sleepy hours" when you only want to see whatever set hours are important to you. Must be some way to collapse those unnecessary hours, etc.
I downloaded this and it worked but now each hour of the day fills the whole page and I have to scroll through all the earlier hours to see some event in the afternoon. How do I undo this action to go back to the original settings?
Run the script again and set the start to 0 and the end to 24. Then open iCal's Preferences and set the 'Show XX hours at a time' setting to what you prefer.