If anyone is thinking about a second wrap, it is not so hard afterall. Needless to say, there are a lot of tapes to choose from, so one of the biggest hurdles is sorting through all of the options.
My second wrap looks just like the OEM black tape wrap job, so the finished job is very normal-looking the way I ended up. Some of manufacturers' packaging for tapes like I used refers to it as cork-filled. Even so, it obviously is a foam-elastomeric material with bits of what I presume to be brown-colored flecks of cork sparsely scattered throughout it. It is thicker in the middle, thins towards the edges, and stretches easily.
What worked for me was learning that I had to remove about a 3/4s width of the original tape from the plug-end of the bars, which is where you start wraping the second tape. Since you begin a wrap by overlapping around the bar once, that already gives you two thicknesses of tape, so removing a bit of the old tape at the beginning of the second wrap works perfectly.
Just butt the second tape up to the reduced edge of old tape, which leaves about a third of the new tape hanging over the end of the bar (that is the part that gets tucked inside the bar by the plug). Start spiraling toward the stem, covering about 1/3 of the new tape with each wrap (i.e., about 2/3s of the tape is left exposed). Lifting up the boots and doing a figure-eight is the easiest part of all because the first wrap is already there so you do not have to worry about leaving any exposed bar.
When you get to where you want to end, if you know to scissor the tape so that it tapers down to the finish line, everything goes smoothly. Using this method, there is plenty of tape to do the job: I had 3-5" left over.
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