What about these posts which consist of nothing but "+1", or "-1"?
I consider these posts to be off-topic because they have no point, but they don't cause much damage, so I usually don't delete them unless the poster posts useless replies a lot or the useless replies are reported.
Other moderators might be more or less strict about this.
And are we allowed to post "bump" with no furthur comment?
Bumping is necessary, so I ignore these. Do not bump more than once a day or many times in a row, though.