As a translator I would like to be able to reuse translations via TM from closely related locales such as de-DE, de-CH.
Those locales are often very similar and may still benefit from reuse each other's content.
Not sure about details. Should every user decide if they want to see those results? Should it be decided once and for all for related locales, as some might have bigger differences than others?
Sounds like a basic matter of checking if the locale has the same language, rather than is equal to the full locale code - and then indicate if it's language or a full locale match.
Indeed a checkbox or similar to say "only exact locale match" would be preferable.
Reassigned to PM
Migrated; check JIRA for bug status: http://zanata.atlassian.net/browse/ZNTA-430