Support making summary_alter work on an array rather than a string?

Currently if module's want to alter a summary, they have to first check if it's not empty to add another '
', then add the summary. Should we maybe enforce that we pass an array of summary strings to the alter hook, so all a module needs to do to add a summary line is do $summary['mymodule'] = t('My setting summary'); and the module will do $summary = implode('<br />', $summary);