[A]ny district, no matter how gerrymandered, has a median voter and a sufficiently motivated challenger can make a good shot at finding him....because voters don't vote (primarily) on ideology; they vote primarily on party, so that in a district full of committed Republicans, capturing the ideological space of the median voter won't actually capture her GOP-loyal vote.
But he's absolutely correct in the main point of his post:
The real issue, I think, is the relative scarcity of campaign funds. If every major party nominee in every House district in America were guaranteed a reasonable sum of public funds with which to conduct his campaign then I think you’d suddenly see all sorts of interesting candidates popping up in “uncompetitive” districts.Absolutely. And, to push it a little farther, even if many of these interesting candidates ultimately lost (as they would), we'd have more interesting elections and a better democracy. For the system, public financed floors for Congressional candidates is a win-win. (I'm for floors, not ceilings; ceilings have a much more difficult relationship with democracy).