All this stuff about landing gear reminds me of a true story.
Some of you know that I work in Customer Support for a rather large aircraft manufacturer, Well one day a telex comes in from a certain not-to-be-named-here foreign carrier. For those of you unfamiliar with very large commercial aircraft they typically have one nose landing gear, one pair of body landing gear and one pair of wing landing gear that are just outboard of the body gear. So this telex comes in and it says something like this:
The airplane maintenance manual states not to raise the wing landing gear while taxing. Why can we not do this? Please explain.
The answer went something like this:
Because the airplane will tip over and go boom. Details will follow in xxxxxxx coorespondence.
Crass? Yes. Funny...hell yes. Better yet, the telex was followed up with a four page detailed telex outlining the pitfalls of retracting the wing gear while taxiing.

Hobo