This has been discussed a few times over the years and is always a point of confusion. One must differentiate between bass and LFE. On most Yamaha receivers (and I'd guess most others), the choice between the "subwoofer" out and the "both" out applies only to the
LFE channel in DD or DTS. It does not apply to "bass" per se, even though it is called that on the receiver. I don't think there is even a defined, consensus definition for what exactly is included in the term "bass" (i.e. what frequencies?). If the mains are set to "Large", then a full range signal will be sent to the mains. The LFE is separate from that signal. If the mains are set to "large", then the crossover that he sets will not apply to them...only to the center and surrounds. That's all that setting does.
In other words, I can set my mains to large and receive the full-range signal minus the LFE information, and I can set the bass (LFE) out to the subwoofer-only in that configuration...the sub then, and only the sub will be receiving the LFE channel information. (I'd still be surprised if the RX-V659 does not have this feature.)
In the reference I gave for Gene's review, I believe he was discussing the feature that allows the subwoofer, in 2-channel, to play all the information below the set crossover point...namely the "bass" (as opposed to the LFE) as MDS has indicated.
But then, as I stated early on, I'm a goofy and easily dazed old man.