Well, that's why I asked. I did it, to change the angles... but I'm running OME which is WAY less that what you have. Plus, I didn't want to have to change the DS. With the Tom Woods DS, you shouldn't have to.
Sorry, just trying to learn. I thought with a DC TW DS, the angles on that side (X-case) weren't so important (up to a point). It was the angle on the pinion side that had to be near straight.
I had a VERY slight vibe at like 0-2 mph with only 1.75" spacer lift. It went away with the BL/MML combo.
However I had planned on doing the BL/MML from the "get-go." I think the BL/MML complements a small suspension lift nicely. The combination allows the use of 33s at a minimum cost.
EDIT: I guess to explictly answer your question: Yes, alot of people do the BB/MML without doing a belly-up. They do it to improves driveline angles and allow fitment of larger tires. It was only with the '03 introduction of "the shovel" by Jeep, that belly-up transfer case skids began to get much more popular. Prior to '03 most people did BL/MML with no belly-up.
I can only guess at the number of people that have gotten some vibes with just a OME lift. My guess is around 20%. Small vibes at that, but vibes just the same. I installed BL/MML and OME at the same time. I wanted no vibes at all (my Jeep is a DD). We'll never know the truth because most do BL/MML at the same time.
I guess since I already have the BL installed, if I get my Medic skids and have vibes then, I could and probably would do the MML to see if it helped.
I mean I was planning on try'n that first if I had vibes being so high as I am now, but I got lucky!!!! No vibes, no bumpsteer.. (Knock'n on some serious wood there)
Since you already have a BL, when you do the MML you will have to put your fan shroud back to the stock position. You also might be able to remove that transfercase shifter relocation bracket.
There are lots of folks running a MML without a bellyup- including myself. Adding a MML will definitely help correct driveline angles. Once you put a bellyup on, you again increase driveline angles and basically cancel the improvement that a MML only creates (but better driveline angle than running a bellyup without a MML).