TVI eliminated with FLEX-6500

A little background. Mosley 2-element triband beam on a chimney mount. I've always had some TVI when transmitting on 15M (even with a 1:1 SWR), whether I was using an Icom Pro (II & III) or my backup Kenwood TS-480. It's understandable since the antenna coax crosses over the Direct TV coax at one point. Anyway, with my new 6500, zero-zip-nada TVI on 15M. I changed nothing, just unplugged the TS-480 and inserted the 6500. This is far from a valid technical analysis, but I no longer need the Bencher YA-1 low pass filter which I used to eliminate most of the TVI. Talk about a "clean" radio on transmit. Now I can operate 6M on the single coax feed from my Rat-Pak antenna relay (which I obviously couldn't do with the LPF inline). Cool....