Well the issue does exist. Honestly, its ridiculous on these forums!
People who have played live demos complain about all the performance issues.
We are then explained that it is an "Alpha build", and by a couple vague developer comments, that most of the performance issues will ironed out in Beta.
And then people say they're stretching the truth, or that there's virtually NO improvements between Alpha and Gold, and that what we see in the demo is what we'll get.

It's MADDENING. I don't know WHAT to think. I need some kind of concrete evidence something has been improved....

I played Oblivion on the PS3 and rarely saw any immersion-breaking hiccups...sure I've seen some, but not worse than other open-world games. Certainly not worse than either of the Fallout games...about the same.
The experiment you conducted is not at all scientific...there are too many variables for it to be a reliable test.

EDIT: Just saw the post by OP that some people say there is almost no difference between Alpha and Gold...that is SO untrue. Alpha is where the easy-to-fix issues, both major and minor, are taken care of. There is a huge difference, not in terms of content but in terms of performance. Also, they will not start optimizing the game performance before Code Freeze, the stage just after Alpha.

That's why you don't feed into the crap people spew on the forums. Only get involved with the positive. Take everything on here with a grain of salt. Spend some of your time thinking about the fun possibilities of the game rather than trying to anticipate the possible flaws. Discussing it is one thing but don't freak on it. That won't change things.