Much as I'm normally one to make fun,
this article about people attributing their own beliefs to God hardly seems worth it. For one thing, you need only look at the arguments put forth by Christian groups against abortion or gay marriage to note that there's a
confirmation bias at work when people try to give God's opinion (for example, citing Leviticus as proof of the sinfulness of homosexuality while ignoring the many other rules of Leviticus pertaining to things modern Christianity no longer views as sinful -- wearing clothing of mixed materials, body piercing, or eating shellfish, to name but three.)
I'd go further than this and extend it past the religious context. I'd hypothesise that most people, if asked to speculate on the opinions of people they profess to admire or respect, would ascribe to them beliefs close to their own. (This would work less well with topics the subject was well-known to hold a specific opinion on, though that in itself would be interesting to test.) Conversely, I'd speculate that people disliked or reviled by the test subject would have the opposing viewpoint ascribed to them.
A good test case would be to ask people what they thought Adolf Hitler's opinion was on the subject of abortion. I'd expect pro-lifers to point to the Nazi regime's eugenics programmes to support a claim that he'd hold the opposing viewpoint from them, while pro-choice people would be more likely to argue that he would eliminate the right to choose by forcibly aborting foetuses from other races while denying abortions to his own people in the interests of growing the native German population.
Really, the more interesting part of the original study would be to ask atheists the same questions, with the caveat 'Imagine a Judeo-Christian God existed as described by the Torah/the Bible. What would his opinion be?'