I imported my tweet archive and now I regret it. Is there a straightforward way to delete it all?
I think it creates a separate blog, much like your test blog, in the Accounts pag. You can simply delete that blog, I think.
That’s right. Fastest way is to delete the separate tweets blog (yourname-tweets) under the Account page. That will wipe all the tweets out at once and you can always recreate it later with a new import.
Obviously be careful when deleting any blog that it is deleting what you expect. Micro.blow will show you a post count and other details before it runs the delete. Wouldn’t hurt to also export a backup of your real blog posts from time to time.