One thing a centre tapped linear pot is good for: more flexibility with a LFO.
instead of having a tri/square switch and a depth pot, you take the tapped pot, run square to one end, tri to the other, ground the centre tap, and now as you turn the pot the modulation goes from full square then less depth of square than no mod then the tri increases in depth. So you have saved a hole (or, you are able to make a mod without damaging the vintaj box). I have a bunch of 100K linear that were special ordered by someone on the synth-diy list, for this application.
That eyelet thing is beautiful, I have to say!! thanks for the tutorial, Dan!