Any way to tell split tool to split at a zero crossing?

Let me start by pointing out that splitting/muting at zero crossings is no guarantee you won't have clicks. The rate of change in amplitude of a waveform (and therefore your monitors' drivers) are at maximum at a zero crossing, and stopping the signal there still creates a discontinuity that will be heard as a click unless the amplitude is also low (which it should be if you're choosing split points musically). A short fade (maybe 3-5ms) will usually be needed to fully eliminate clicks where there's significant amplitude around the zero crossing.
 
That said, I've found that Snap to Zero Crossing seems not to be working in lanes except for slip-editing clip boundaries. All tools snap to zero in the parent track as expected, but selections, splits and comps are not snapping to zero crossings in lanes. This may have come up before. I haven't checked to see how far back it goes, but I know there have been complaints about failure to snap to zero in previous versions.