A waveset is three zero-crossings:

Waveset Interleaving takes two inputs, and interleaves the wavesets, or groups of wavesets, that it finds in those sound-files. For small groups of wavesets, the result can be extremely 'noisy', bearing little resemblance to the original file. However, at larger numbers (say 20-50), interesting 'spikes' of sound from each file can be heard:

Number of wavesets in a group: How many wavesets should be in each succesive group to be interleaved
Mix to: Whether the new sound-file should be created in a new channel in the same document, or a new document.
Interleave: either alternate groups (roughly the same length) or every group (twice the length).