Re: Some additional requirements for the ScriptProcessorNode ..

Our implementation identifies nodes that can never affect output in the
future, and automatically removes them. As far as I can tell, we do this
without altering any observable behavior --- except for performance I
guess. So we may wish the spec to say that implementations should optimize
for cases where nodes are added to the graph and never explicitly removed
even after they can no longer affect observable output. I think attempting
to fully define "after they can no longer affect observable output" would
be unnecessary and a mistake.

For ScriptProcessorNode, this would mean an implementation can never
automatically remove a ScriptProcessorNode. I think that's OK.

Rob
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