It turns out that the cells I was making MIV-competent were growing immensely slowly. RR's last comment said if all my optical density (OD) points went through an exponential line, I had started with a small number of viable cells. Alas, this was not the case. Bring out the graphs!
As you can see, the points aren't quite exponential. :S Why? Well, I am indeed running growth curves today for KW20, RecJ-, dprA-, and RecJdprA-- strains. It's been about 3 hours, and growth does seem quite slow. I'm also planning to run a gel on some DNA I made a few days ago. I extracted these chromosomal DNAs from the RecJ-, ExoI-, and RecJExoI-- strains I made from the Oxford DNA. We're going to check them with PCR (my primers are here!). I also read over Josh's blog post on linkage. I'll have to reread it to understand it better (it's not your writing, it's me :]).