LML E86B Questions

I've been toying around with stock tunes for LML for a little bit now, and am curious if someone can help explain a little of what I'm seeing.

1. Real quick educational moment. I understand all of the segment numbers need to match for it to be a "stock" tune (i.e. 12660403) and work for one's truck; however, I noticed the checksums were different between the various stock files I have that do match all segments, and what EFI Live shows is on my truck. I know I personally can't get the stock tune read from my truck, but I'm reading the calibration numbers.

Does anyone know if that matters, of if that is just how it works since they have to read it out? I'd think the checksum would be the same if the file was read and saved without modification.


2. In the T87 tranny tune Table D5196 exists a Torque Control map. Below is a screen cap from the stock tune noting the torque is up to 760 ft-lbs, which kind of agrees with info found online 765 @ 1600rpm). It seems without modifying the tranny tune that the ECM may try to follow its tables (if they get modified), but then the tranny will just dial the ECM back somehow - haven't looked that far yet:
Attachment 24310

Then in the ECM tune, there are two RPM to torque curves. Table B0441 seems to generally agree with the transmission table above at least with the max being at 760, Table B0443 is blocky and different - not sure what that's all about just yet. Both shown below.
Attachment 24308Attachment 24309

How is it that people are getting increases in power (HP and torque) if they aren't doing a transmission tune as well?

3. How are people "calculating" the HP tunes they sell? I don't think they are dynoing all these various combinations, so when someone tells them they have CAI and some other mods, I assume they are either using a shelf tune they previously wrote.

4. Anyone use the Timing Calc V4 with the LML table added? Any pointers on it?

I appreciate your help.