As for implementing substantial changes to soundfiler, I think the way to do it is not to try to get the modifications into Pd-vanilla, there are so many issues of backwards compatibility. Instead make a new object, even if it is largely just a modified version of the original. [sndfiler] is a good example of that.
as i mentioned before, sndfiler works around one limitation of soundfiler, but is unable to work around fundamental limitations of pd's architecture ...
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