What he said
There are quite a few cards which have "would" with only an implied "instead". I think that the police backup is clearly one of them, and you destroy them instead of discarding.
What cards are you thinking of? Generally, >G tells us to read the card text as literally as possible; we should probably not imply any "insteads" unless they've specifically told us to with the card in question (Jack Handle being one of these).
Had a bit of an awkward thing come up yesterday which I wasn't sure how to resolve - Police Back-Up says that whenever a villain card would make a hero discard, destroy Police Back-Up. We were fighting Gloomy and he had his Tome out, which says that at the start of his turn each player may discard to reduce the damage dealt by Gloomy immediately afterwards. This isn't making a player discard, since it's an optional thing, so I wasn't sure whether someone trying to discard would destroy Police Back-Up. Plus I'm stil not sure whether Police Back-Up gets destroyed instead of a player discarding, or as well as. And I wasn't sure whether, if Police Back-Up went instead of a hero card, that would count toward reducing Gloomy's damage when he attempted to hit everyone afterwards. We ended up just ignoring the Police for that aspect and discarding as normal. Fortunately Rooftop Combat came out the following round so we didn't have to worry about it any more, but it was still a bit confusing, lol.
If you discarded for it Police backup would be destroyed, because the discard was the effect (optional or not) of the villain card.
We can petition Arenson to put the question of whether the discard is prevented by police backup in the questions list, but I'm pretty certain it does not prevent it.
Maybe someone with enough time should go through every card that has a 'would' trigger which does not have an explicit 'instead' or 'also' or a clearly implied 'also' and post them up, so that it can be determined for certain which ones are 'also' and which are 'instead.'
Speaking of "would" triggers, the rumor is that Christopher has a clarification to the Fortitude/Super Human Durability ruling. Thats what the Essen folks have told me. Maybe we will get a better sense of what "would" actually means when Christopher decides to drop in and finally put that issue to rest.
Am I the only one who thinks that "would" is not a mechanic, but just the clearest way to write something?
The intent is unlcear at best. And as with all "ambiguous" situations, the rulebook leaves it up to player choice (though that rule probably was not writen with this application in mind).
The clarification to Fort/SHD should really point us in the right direction with how to best interpret "would" found in trigger clauses.
(@Christopher, we are ready for that whenever you are! 
)
I had figured that 'would' triggers occur before the action and have the ability for the action to be canceled, whereas triggers without 'would' occur immediately before or immediately after the action (likely the latter) without ability to change the action.
I have always understood the SHD/Fort ruling to mean that "would" is not a mechanic (i.e. the word "would" doesn't desigante a specific acting time).
"would" seems to be used in one of 2 situations, to make the intent clearer:
1) When an action is being replaced. Meaning, don't do X, do Y instead. (This inherenlty means the action didn;t happen, not that "would" puts it first.)
2) When a static effect has a trigger. All DR is static, but conditional DR would have "would" (e.g. SHD, Shielding Winds, etc.).
While I will eagerly wait for Christopher's ruling, I honestly don't think it was understood wrong, just that he is changing his mind (like rule #15).
Nope. 
And that point is still unclear. It depends on if the word "would" actually changes whether triggered effects are considered "simultaneous" or not. Because if "would" in fact does not have an impact on the status of whether effects are simultaneous (such as the status of being dealt damage and would be dealt damage), then your view of "would" has to change.
The sooner Christopher shares this clarification the better off we all will be. I have to think its coming soon. I am getting antsy.
There are 30 cards in the game (to this point, I'm not a playtester but I have everything that is out).
Of those 30:
12 are redirection, they do not say instead, but the instructions clearly state what to do with the damage.
8 deal with increasing/decreasing or preventing damage, and again the instructions are clear as to what to do with the damage.
4 have instead written on the card
1 are Ambuscade's traps, they share the same wording and it is clear since they tell what to do with the trap, they don't need an instead.
3 have no instead, and the triggered effect doesn't deal directly with the cause but have clearly worded instructions (Kismet's Inconcievable Obstruction and Lady Luck, La Capitan's split across time side) that do deal with the initial trigger.
The two remaining are Police Backup and Jack Handle.
The four with Instead on the card are Null-Point, No Executions, Unforgiving Wasteland and Spite's Drug Wracked Monstrosity side. They all deal with a triggered effect that doesn't effect the initial trigger, except that they do say instead, letting us know that the initial trigger doesn't happen.
Jack Handle to me is a mistake of wording stemming from it being in essence a redirection of damage. All redirections use the word would, but they all use the word redirect. Jack Handle doesn't, which is confusing and makes it need an instead which it also didn't get.
While this doesn't give any smoking gun style evidence, it gives us several examples that >G has written of cards that have trigger effects that don't effect the initial trigger, but have wording added to make sure it does, sometimes instead, sometimes just with giving clear instructions.