They are not designed to be platforms to lay bare one's soul.
I don't see why not. To be honest, what other choice does a public figure have? What other vector of communication can they use to personally address what amounts to personal attacks on their character?
I think you are partially correct, it is foolish to assume that what these people put out in their speeches and public addresses is all that is in their heart, but at the same time it is also foolish to assume that nothing can be learned or effectivly communicated by these types of speeches especially when you take into acount the total picture of how they run their public lives. In this case you can take the speech in the context in which Obama has run his campaign.
I want someone who can really get something done. Can he do it better than Clinton or McCain? That is the only thing I care about.
That is where I think it is the responsibility of the public to excercise broad judgement. The point you bring up is historically why governors have faired better than legislators in races for executive positions. It is much harder to tease out the accomplishments of an individual legisator because they are always affected by the backdrop of the body in which they served. An executive canidate often holds the edge because they have more opportunity to exercise independent will.
Since we have 3 senators running, the playing field starts sort of level. There are more years of experience for McCain versus both canidates but in Obama versus Hillary, Obama actually has more legislative experience than Hillary.
I also take into account how the various canidates are running their campaign. Obama has built a mammoth system and has surrounded himself with advisors that are the best of the best (Susan Rice, Samantha Powers (he shouldn't have ditched her)). Compare that to the short sightedness of both Hillary and McCain, the various times they have had to dump staff for ineptitude and in the case of Hillary they still don't even get along with each other.
Obama has managed his money, kept his campaign extordinarily focused, shattered fundraising records not only in the total amounts but in the amount of people he has empowered to be part of the process. Over 1 million individuals have donated to his campaign. He was smart enough to tap modern avenues to get his message out that the other canidates started to mimic only after they saw how effective it was.
Can he lead? I think how you run your own house refectly directly on how you would run your business or your office.
Of course, biblical creationists are committed to belief in God's written Word, the Bible, which forbids bearing false witness; --AIG (lest they forget)