I think that the hand - down should be avoided for it makes pressure and may condition the writing in the topic . On the other way , leaving just the hand - up alone would mean that when a topic is really important for you , well , there you go .
No need to bring anything down , what is the point ?
Plus on my view it can bring discouragement for writing again and the rising of an incomprehensible elite membership that could ruin the joy of the community .
I think that the point is to avoid the confusion between discussions and polls .
Topics are for discussions and not for voting what you like.
To do so there are the Polls where you can clearly express what you like best .