Things You Learned from watching Excalibur
1) Never show a King that you have a more attractive wife than he has (See The Tudors also for additional proof!)
2) If a sword ever becomes stuck in a rock, ask someone who hasn't been walking around all day wearing very heavy armour to try pulling it out, they may still have the strength to do it.
3) When making a deal with someone, first get the details of what is required from you before swearing on it.