Bias does not automatically mean a statement is false.We don't know if his opinion was biased or not. It could have been.
Find me were his statements about TUA were false and then we have something to talk about! Otherwise I have to assume if his statements weren't false and he has a good general background in football, the only reasonable assumption left is that his statement are true, i.e. accurate.
His being a friend of Tua no more defines his statements about Tua as being biased then most "talking heads" statements are, at the very least, untrustworthy.
William's bias can be against the people that would suggest Tua is not or will not be a good NFL QB or his bias could be for his friend that he is sticking up for. I am not making a judgement on which is the case, time will make that determination.
That's why I said this: "The fact Williams knows Tua personally compromises his opinions" This is a statement of fact and it has absolutely nothing to do with what Williams actually said.
I hope that makes sense...