I suppose that's true, but on the other hand, to use the chord builder for this particular purpose (i.e. not really what it was initially conceived for, I'd wager) has its limitations too. For one thing it rather depend on the user having some elementary notion of the connection between the sounds and the chord's names.
On a keyboard you can e.g. change just one note with your finger and instantly hear if you're getting closer to the mark while the name of what you did doesn't matter one bit, whereas attempting to do the same - while at the same time having no idea what the chord names in that interface actually mean (not even that a "minor" chord means that a certain note of the chord is a half-tone below a "major" chord!) - will have you face a helluvalot of some very random guesswork.
And again, are you sure you can't somehow use the computer keys to play that Big Piano thing? I haven't found a way, but if there is one I very much would like to know about it!

p.s. Maybe this just requires some designated implementation of something new by PG worthy of a request thread...

Just because you can, doesn't mean you should!
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