Dear AV/FPTP debaters.
I know making analogies are hard, they're perfect tools for representing the complexities of voting systems in "every day" ways, but they're being abused, misused. Right now, if they were living things we'd have a government task force cracking down on this abuse right away. But they're not...so here are a few handy hints.
Choosing your setting
When talking about FPTP or AV you are talking about voting systems where multiple people are making independent decisions that will affect a change or direction for one thing that affects all participants. An accurate example may be multiple people choosing where to collectively go for dinner, or multiple people deciding where to put the printer in the office.
It'd be false to have multiple effects in play, as this wouldn't represent the "MP" factor of the single member constituency.
Talking about preferences
When you vote you put down an X under FPTP, or a list of preferences under AV. No matter which way you vote you ultimately choose to put a mark next to a candidate, or to not put a mark against a candidate.
If your analogy starts to talk about levels of "care" or "weight" then beware! Ensure that you are being fair with your analogy and using this weighting in the right manner. Whether talking about FPTP or AV, you can never know how much a person "weights" their own choices. You can compare internally but not externally.
For example, I can say with full confidence that person X prefers radishes to sprouts, and person Y prefers lettuce to radishes. What I cannot say with full confidence from this information is that person Y cares less about radishes than person X.
If your actors in the analogy are making decisions, when talking about a voting system, they aren't discussing their individual beliefs with each other...they are making a statement for a single candidate. As soon as your analogy starts to compare actors' influences or intentions then it is no longer analogous with a voting system.
Adding time in to your analogy for AV should be frowned upon, but isn't always wrong. As long as actors do not change their choices, and act honestly, then decisions can take place in either an instant run off or a normal run off manner. If you find yourself in a situation whereby actors are using previous decisions made in the scenario to inform their further decision, then you too have left analogy-land.
Use these basic principles and go forth! Make your own analogy garden full of happy examples and representations of reality; free them from the abusive shackles to which they're currently cruelly contained.