Having seen quite a few pitches myself, one good thing you can do is point out your major flaws/obstacles before you're asked about them (assuming they don't clearly spell out your impending demise).
This may seem a little counterintuitive, but it lets you present the issue in a better light and explain how you're going to fix it, instead of having the investor feel like they've discovered a glaring weakness that you were trying to brush under the table. I believe lawyers use a similar technique.
One caveat to this: I'm a blogger/reporter, so investors may have a different perspective. But I'm guessing it holds true for them too.
In my experience, few people are able to assess themselves effectively; it's too easy to slide in one of two directions: avoidance or neurosis. But as the saying goes: the unexamined life is not worth living.
I tend to think those people who seem crippled by self-doubt see just as distorted a picture of themselves as people who are incapable of self-examination, just skewed the other direction. Minimization vs maximization of faults.
I was involved in the hiring process for faculty members in academia, and our approach has always been to invest primarily in individuals, rather than in ideas. Ideas are disposable, and competent individuals will quickly learn how to adjust their ideas to the circumstances.
Case in point: Jason's own product Code Historian (see blog post above).
I understand the difficulties that come with 100's of applications. The admission criteria always end up being far from ideal. In my former academic circle, we relied heavily on letters of recommendation; both who wrote them and what was said about the candidate mattered. Everything else the candidate wrote was only glanced over.
I would think something like that can be more effective than meticulously analyzing someone's pitch.
Paypal's original idea is still a problem for people and it's similar to what Square is doing now.
Flickr's original idea is lot like the social MMOs we see now like FarmVille and many of the other Zynga games.
If you're right and the ideas were indeed ahead of their time, that means they were still a bad business proposition (at the time). The founders should take full credit for realizing this and adjusting accordingly.
However, since they were ahead of their time so pivoting was the right thing for them at that time.
I think you'll find when reading the individual posts on each topic that it's not contradictory.
Also there's a distinction between seeking things like competitive advantage -- which of course you have to do -- and going ahead and doing something regardless.
That is, "just do it" is the prime mover, but of course you have to be seeking things like happy customers, competitive advantages, ability to describe what you do in 30 seconds, etc., as you go.
Also remember this is in the context of pitching investors, at which point you do need some ideas -- you can't pitch "I'll just try stuff."
I think that's a corporate perspective to review a startup pitch. In a startup you're iterating and evolving your idea but you have some start point and perhaps it's your 'idiosyncratic preconceptions'.
I see a lot of these issues all the time, but sifting these out and articulating them this concisely is very difficult.
I can also see these issues created the biggest challenges in previous projects I have worked on.