Dan,
I think you can be biased toward your own natural ability to observe, absorb, process, and then infect your next work of art, and be assured that this process you undergo will allow you to impart your very best efforts on the matter at hand your present work. I would not go quite as far as Miles Davis, who never looked back at his work, and I think hated to even listen anymore to the album he just released, but I do think a completed work of art is hard to look back on because it is a past relic of this ongoing process so the real enegy and focus is on what is ahead.
Now, the bias or confidence or whatever you want to call it comes from knowing that you have internalized your past work, and that you continue to internalize other works by others in a way that will feed new energy and thoughts to the next work. So in a way the past work seems dated and slightly out of step with where you are going.
To be consumed by what you have done, possibly meaning to be biased to your past work, I think endangers you by possibly causing you to fall back on paradigms, thus stunting your growth. I think people that fall prey to their own press, and begin to believe the good things others say, could risk stagnating in their own glory, and begin repeating what they think are absolute qualities, when in fact certain qualities, or bias, are merely temporary stages on the road to something quite different.
I do not think it often that someone has the "Road to Damascus" experience, rather it is a very slow evolving process that causes architects to create great works, to make a career that consistantly produces great works, because they have delved into a special process of creativity through which they constantly grow their ideas, and never fall back on old true and tried ideas.
That analysis takes time to uncover, and is usually why most people whom are considered giants of their profession are discovered later after they are gone, and those people whom are considered great, or fashionable at the present time they are creating often fade with time and are largely forgotten.