now, signal-to-message objects _should_ accept this scheduling, by *not*
sending messages in the dsp callback, but rather schedule them to the
next tick (via a "[delay 0]")
afaik all _internal_ objects adhere to this.
hm, again.. so, at what point do these invisible '[delay 0]' objects
output their messages? do they end up at the 'head' or the 'tail' (so to
speak) of the 'message avalanche'? or are they somewhere in the middle?