edit: I felt something was off and doublechecked, I had misremembered the rule on dashes, and consecutive dashes in urls is apparently fine, and will depend on the registrar allowing them or no

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yes, non-punycode domains may not start or end with dashes and must not have consecutive dashes

the consecutive dashes in punycode were done on purpose so that the new internationalizing punycode domains couldn't conflict with any existing domain.