I just had a torrid time in my manual drafting class. It was a complete disaster! After projecting the whole drawing on the chart, I found that I made a mistake in my first projection, as a result of which the whole thing was wrong. The engineers who drew technical drawings using manual drafters before the advent of computers, must have been really skillful and must have had bucket loads of patience. You truly appreciate the power of CAD after attempting a complex manual drawing.