It's the perception problem — a perception of liberal bias for which I haven't found any evidence after checking with editors at the paper.
He checked with them and they said there was no bias, so there!
Well, there you go!
Who're you gonna believe? Byron Calame, or your lying eyes?
Calame's predecessor in the ombudsman-without-ombudsman-powers role at the Time, Daniel Okrent, also went way out on a limb to deny any institutional slant or bias. In the end all Okrent's tour as Public Editor did was damage Okrent's personal credibility.
Calame, of course, comes to the job with less neutral a record than Okrent, so he has less credibility to lose.
As far as making corrections in their blogs instead of their print columns, the dwindling number of print edition readers mostly read the Times to get their lower-Manhattan liberalism reinforced. They're not interesting in hearing about errors by the likes of Krugman, they think the sun shines out of Krugman's rectum.
Which we know is impossible, as his head and shoulders would eclipse the thing, and since he's only 4' 10" tall or so, the sun would only shine at a very low angle.
d.o.l.
Criminal Number 18F