"and if over-confidence was the issue, then why didn't ben just yell, "No, Anakin ... you'll never make the jump!" Tossing out some vague new battle strategy involving "high ground" is, at best, another awful choice of explanatory dialogue. At worst, it's a cop-out."

Because Anakin would make the jump - he would just never complete the landing. Obi-wan tried to give him fair warning, because HE DID NOT WANT TO DO WHAT HE KNEW HE HAD TO DO. Obi-wan was trying to stave off the inevitable, and Anakin forced his hand. Not to mention the "high ground" could also be a metaphor for his moral standing - "you can't defeat me because I am fighting for good."