The issues that we (as keyers) had with the software in development were virtually impossible to address, given that there were several corporate layers between the contacts. The one time that a load of developers came to our data centre to observe keyers in action, one of our quick-thinking lower managers managed to snag a contact detail and for about a month there was an easy option to get small niggles fixed.
oh, btw my tph was 2-3000 so I don't know why the USPS workers are so slow. Actually thats just boasting, I probably do - it is likely that the software is a whole lot better than it was, which means that the quality of the images that it cannot handle has gone right down and takes longer for a human to process as a result.