performance of tuple-less Python?

[Greg Wilson]

Has anyone ever built a version of Python that didn't include tuples, and
looked at the performance of code that consistently used lists instead?  I'm
curious as to whether the use of tuples (which I believe are conceptually
redundant) actually has a significant positive impact on the interpreter's
performance on non-trivial codes (i.e. once caching, instruction ordering,
and all other effects have come into play).
Thanks,
Greg