Obviously banana jacks can't connect to the track. 
Considering the discussion that resulted when that topic came up a few times earlier in the thread, I considered that a benefit rather than a hindrance.
If one can't easily attach the probes to the track, one is less likely to try to use it that way and then wonder why the results aren't what's expected.
I used regular Digikey prices when suggesting what the jacks would add. I didn't try to go to eBay for direct from Asia pricing or anything like that.
-Dave
