Was I setting transients incorrectly in prior versions?
This transient placement seems early to me:

My method of warping this track (Jori Hulkkonen - All I See Is Shadows) is as follows:
1) zoom into the very first beat
2) create a new transient at the start of the beat
3) right click the transient & select "Set 1.1.1 Here"
4) right click the warp marker & select "Warp from here"
You can see how Live detected the first transient very early, and how I set the 1.1.1 beat:

This new method of warping seems very similar to previous methods, except now I also have to modify transients as well as warp markers.
I would expect, in the first screen shot above, that the transient would be directly at the beginning of the beat (similar to my 1.1.1 placement), and that I'd simply drag the transient at bar 69 so that it's line with the time ... But since the transient detection is off as well, I have to create the transient and then drag it to be in line with the time.
I suppose that if I just assumed the transients were placed correctly throughout the entire track (so, if I didn't zoom in so far), then the entire track would be "mis-warped" exactly the same (which would make it OK) ... But that's only OK if Live consistently mis-places transients in the same manner/amount every time (so, if it ever warped a song with all of the transients placed slightly LATE in the beat, then everything would sound as if it was SLIGHTLY trainwrecked).
So, am I doing something wrong / being too detailed / expected to place transients all over the place?
Thanks for any help/suggestions on this!
---UPDATE---
I converted the MP3 I was using to AIFF, and tested the same method outlined above with the same results - so, this does not appear to be an issue isolated to MP3 files.