Not saying this is going on in this thread, but it's maybe headed that way:
http://en.wikipedia.org/wiki/No_true_Scotsman
On one hand it's fair to question specific beliefs but I think one has to be careful to make sure to address people and their beliefs specifically. I wouldn't, for example, question a Christian or Christianity in general based on the actions of those crazy people who picket funerals.
However I'm going to be careful not to let people slip into the No True Scotsman fallacy.
The question then is how big a chunk of Mormons actually adhere to the beliefs in question? Or someone who actually believes them respond.