A VETO should be used once people DO realize what a vote means, so they can judge that a change has unacceptable results.
If the caller of the vote repeatedly refuses to explain or document his change, or refuses to provide sources, if needed, or if a request to hold the vote until explanations are given is not honored, you may likely resort to a VETO as a last resort.
Whimsically using a VETO to stop a vote because you do not at first understand the ramifications is, as written above, a violation of the rules..
Curious, if you are in this traject and you are seeing your veto comming closer? Is there a way of give some pre-waring? (this is in NO way related to this thread, but i've found myselve in such a position).
