I am not crazy I am going to ask to see if I can use Strongheart Vest but I am not going to count on it since I know he has a copy of 3.5 FAQ on his laptop. So if he reads it in black and white that it flat out says it only works for attacks, how can I argue?
Just tell him that:
1.FAQ is no reliable source and arbitrary/incoherent in their answers.Provide examples for that, just to on the safe side.
2.One could argue that abilities are always split into fluff and crunsh.The first part about "defends you vs attacks and such" describes the effect but does not state the effect so it would probably be fluff.The second part on the other hand only states what it does so it would probably crunsh.(I am not a big fan of this way but some people do it so might as well mention it...)
3.The consequence of having the vest only protect vs. attacks are absurd.Having it only protect vs. attacks implies that the vest would be omniscient in a way because it has to "KNOW" what is an attack and what is not.And this is not how generally things work in 3.5 where world coherent realism was still an important factor.
This might be hard to get, but take this as an example:Would Pinocchio`s nose grow when he states: "God exists." for example?Probably not because his nose is not omniscient and does not "know" whether the statement is true or not.(Kind of a weird example but I hope it clarifies things)
4.The DM obviously does not (or should not
) use stupid things in d&d (for example if you build a row out of n people and everybody readies their action to pass a stone handed to them,the stone would pass n people withing 5 seconds(brainlag,forgot how long was a round in d&d))
And even though this(the vestment case) stands in the FAQ this would be also one of those stupid things so he should probably allow it anyways.
Just some points in which direction you can go.If you want to I could bring some more up but those where my initial thoughts.