Disconnecting the battery could help, but it also just as easily may not, or any "improvement" may only be temporary. The integrator function of the PCM is suually fairly tolerant of changes, and will update the block learn with any parameters that are within the acceptable programmed ranges for feedback sensor inputs. Since you are not getting any MIL (Malfunction Indicator Lamp) the inputs are likely within an acceptable range, and the PCM has probably already "learned" any changed operating parameters. Disconnecting the battery MAY clear the tables and force re-writes, but the data may end up being about the same. It can't hurt, so long as you do not have the Theft-Loc on the radio enabled and the TDM does not lose any transmitter codes. You would actually be better off by removing the PCM power fuse(s) and leaving the battery connected to back up all the other devices.
I'm guessing it's time to take a close look at the ignition and fuel delivery. Usually, ignition events are closely monitored by the PCM, and misfires are detected easily. That leaves the fuel delivery system, which is actually not monitored that closely by the PCM. Poor injector flows, poor spray patterns, high propagation times for injector pintles, and other fuel delivery problems aften go unreported by the PCM until they cause a more significant problem.