If they simple include a FOV setting somewhere easily accessible (like the other text tweaks) it's a non issue, since everyone can set his FOV to whatever he wants or needs, independent of his screen size. If people want to run around with an unrealistic wide 128 (current maximum allowed) FOV, let them do it.
I'm fairly sure the previous FOV hack for M&B will also work in Warband right now, so even now some people could give themself "an unfair advantage".
I just don't want to use that hack since editing values in memory is messy and complicated. But ultimatley what the Devs would be doing is just to give a clean official way of doing what is already possible anyway, and what the game seems to accept just fine (no bugs with wider FOV).
If you look at Armed Assault - the best "first person simulation" currently around, zooming in AND zooming out is an integral part of their game concept. Because at the heart of it, not even a 16:9 widescreen gives peripheral vision anywhere close to real life, and even zoomed in to 30° does not give accurate resolution of small details as in real life. Changing FOV is merely a way of allowing both "wide overview" and "close detail" on the same computer screen, which is never as good as our eyes.
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