<p>Merging is difficult (impossible?) to reverse and so is used only when the questions are such close duplicates of each other that all the answers to one would read acceptably as valid answers to the other.</p>

<p>Perhaps more merging should be done, but since the decision in each case requires  comprehensive review of both threads, careful thought, and great confidence in the correctness of the action, I usually am reluctant to perform this unilaterally.</p>

<p>Maybe merge proposals should be made here on meta as each case comes up, and debated and voted on by the community, just as tag synonym/merge proposals are.</p>
