Nutsnbolts, I use ONLY the low-pass cable pair from the bass modules to the towers and tie wrap the high-pass connections back against the low-pass cables so that I don't get any shorts (bent back so that the powered ends won't contact with the non-powered leads).
I agree, the directions could have been written better. Maybe the same engineers who designed the speakers should have drafted the instructions. I'm no expert, but I think that only time you would technically need to use both the low-pass AND high-pass cables would be if you were using a bi-amp configuration, separate leads would then be necessary. I took a look at the Streamline Tower user manual just to check. Here is another direct quote from the towers manual...."Standard Hook-up (Non Bi-Wire): For Towers without Bass Modules: For non-bi-wired systems, connect your cables to the upper terminals and use the supplied jumper straps between the lower and upper terminals."
So, if the towers are powered with only a right and left cable going to the "upper terminals" after the jumpers are attached, then a combined signal from the bass modules should follow the same guidelines. I think I have confused myself here... what I'm trying to say is that I think that the bass module uses it's internal crossover to separate out the lower frequencies and the remaining signal is then passed to the towers as if they were getting the full spread, sent from the "low-pass" output to the jumpered towers. I've had a couple of glasses of wine, so I hope this makes sense.