Here's the thing - "GeoProcessing" as a concept has multiple implementations, and while many times they can be "equal" in terms of output, they are very different in terms of audience and situational constraints.
For example - in my opinion, ModelBuilder is evil. This may or may not be the actual case, but since I come from a coding background, I'm highly skeptical of any draggy-droppy code magic thing. I do however groove with Python, and massively appreciate the productivity gains as compared to ArcObjects.
And similarly, for people who come from a pure "GIS Analyst" background, never to have their minds corrupted with the various incarnations of ITopologicalOperator, ModelBuilder is pure awesome.
By lumping these two types of users and the associated tooling into one forum, you're doing a disservice to everyone. Forums only work if they are quick and easy to use, especially for the power-users who are likely to actually contribute answers to the conversation.
So - split'em...
Forum a) Draggers & Droppers (The Dark Arts of Model Builder)
Forum b) White space matters (Zen and the Art of ArcPy)
Cheers,
Dave