Ignoring OS is the only way to make a fair comparison, since OS preference probably trumps the feature and price delta ( whether you prefer WP or Android).

The only way to fairly compare devices is to ignore the single most important aspect? No, I don't think so.

The single most important factor is also the most subjective. I personally dislike Android and wouldn't use this phone if you gave it to me for free, but I can still respect the price for hw. I'm surprised this even needs explaining.

Have you ever used Android 4.2? This phone ships with a new OS version that I don't think is out anywhere else yet. How do you know in advance that you will subjectively not like it? I hate Windows Phone 7, but I wouldn't dare say I hate Windows Phone 8 since I've never seen it IRL. How could I make such a judgement? It's not purely subjective, either. What's the point in having more RAM or a bigger screen if the OS doesn't handle those well? Or, if it handles it exceptionally well, that should be noted as well.

Android 4.0 is reasonably similar to Android 4.2 for many people. Just as WP7 is reasonably similar to WP8 too.

Then why bother comparing. It is a classic apples and oranges then isn't it?

The whole point is to compare the hardware to see how price competitive the phones actually are.