Note: I consider it a breach of both rules 1 and 4 to use the word "courtesy" in the animation sections. That sentence is the only exception. The word will be removed wherever it is used and a warning given to the offending poster. If I see the same person do it again after a warning they will take a temporary ban. How many times the ban will be temporary depends on my patience, which I do not recommend you test.
Justification:
It should never be necessary to whore your thread out in this way. People are perfectly capable of viewing all the animation threads, and you should assume that they have unless they have not logged in since you posted. If someone has not commented on your animation then they have nothing to say. Asking them for a comment will not produce anything helpful and thus will create spam.
Also, by asking someone for comments at the end of your comment in their thread, you are implying that the only reason you commented was attention seeking. This is especially prevalent if the comment you gave was anything less than a complete cc. This is spam in itself.
Furthermore, if we end up in a culture anything like what has developed on darkdemon then we will be in a situation where the only way to get any comments at all for your animation is to ask for them. That is not a community, that is a marketplace, and they tend to be much more unpleasant (trust me, I'm an economics student). This place is built upon the friendly and helpful atmosphere. I will not see it demolished by The Word, as it has been in some places.
Lastly, by creating a situation where you are expected to respond to criticism in a like-for-like manner you are essentially forcing the other person's actions. Not only is this, to some degree, immoral, but it makes the person you are doing it to slightly resentful which will impact upon the quality of the criticism. There may also be a feeling that a good comment should be reciprocated, even when the quality of the animation being criticised is poor. No beginner will ever improve without being told more that "great job".
I hope it will never be necessary to enforce this.