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Why even erase accounts at all? Just rename them to randomized names with a prefix.

Tumblr's method is to append "-blog" to the account name. Still discoverable.

How do you find the account again?

A link to a tweet would do it. And if they're in any lists, those lists could show the old name too.

You could also keep the old name (or most of it) as the start of the new name.