If you're that frustrated it might be better to wait, but, I've replied to some during the challenges and tried to say something like, "I see what you're saying, but I kind of feel this way..." and let them have their opinion. They are entitled to that.
I've also thanked people during the challenge for their comments.
I replied during the desolation challenge because of a comment suggesting my abandoned building didn't meet the desolation challenge criteria. I thought it was my duty to all other DPC'ers with abandoned buildings in the challenge to enlighten this person. It is not really a good idea to respond to a comment during the challenge but I would think that the comment shows that something untrue was assumed about your photo, I might be inclined to make the correction and not wait.
I do not like to reply during the voting, however, on a recent challenge, I did PM a person who made a comment on my submission because he was pointing out a problem in the shot that I could NOT see (literally - it was a monitor issue!). I just couldn't wait until the voting was over to know what the problem was - I wanted to go ahead and put myself out of my misery! The person was very kind, and VERY helpful in his reply, so I was grateful for the input.
I occasionally reply during the voting, especially if the person has a direct question. It's hard to remember to reply afterwards, but if you do, you will probably get more comments.
If a person seems to be asking a question that may cause them to re-evaluate their vote, I will reply. If they are just asking "Where was this" or "How did you do that", then I'll wait to keep things anonymous.
I only answer if they are asking for clarification on something.
JD
I feel it is appropriate to respond to questions whenever they are left. I do not feel it is appropriate to respond to a comment that isn't specifically asking something until after the voting is over.
So...
"I don't see how this meets the challenge. Am I missing something?"...
I would respond with an answer.
"Does not meet the challenge =1"
I would not respond.
That said, please make note of my signature... It's not just a signature, it's a disclaimer :)
I like to read comments on my work, but one that I recently got was vague. I believe that they voted low, but there's no way to tell. Comments like " composition is not that great" without being more specific about what part of the composition is "not that great" is not very helpful.
i hope your not talking about me spaz...but if you are let me know =`) I try to be as specific as I can in my comments, but since I TRY to say something about as many shots as I possibly can stand, sometimes I might be too vague.
I agree with myqyl on the strategy - if the user genuinely has a question, go ahead. But don't campaign for a revote on every bad comment. My two cents. That and a dollar will get ya....well not much...
If I get a comment from someone who really genuinuely seems interested in something I did, a technique or something, I will freely respond. Even if they just make a remark about something I did, I think it is fair to respond to that. Its definitely not a plea for a higher vote, just answering a question. My opinion is that if I answer right away, its still fresh in their minds and probably would be the most useful (if indeed I said something that might be useful) right then and there. There was one challenge picture for symmetry that I responded to a couple comments wondering if I'd submitted the picture upside down, which I did do. I was quick to commend a person for even considering it. Of course I'm sure some of that energy came from the fact that my score was over 7 most of the week.
If the circumstance is such that the main element of your response is not regarding anything with scoring, but answering a question or revealing a technique, I think it is okay to answer during a challenge.