Two for one applies here as well so you really need to learn to use "the button" if you cannot give relevant and constructive criticism. Failing this, you run the risk of being rejected!
We generally ask for feedback to make our site better so please don't blow smoke just to say something. You will be wasting our precious time and efforts. again, learn to use the secret button.
Pay attention to the type of feedback that was requested. It does not help giving feedback on the use of pictures when the request was for Site design.
Don't be scared of hurting the Affiliate's feelings, after all, they asked for the feedback and are expecting to be told, politely, that you think that something else could possibly work better. We are all open to criticism that could improve our site and, by implication, our income.
Even experienced members seem to be failing at this and give me Semi poor comments. They have a semblance of structure but are still commenting on layout design and other stuff a natural person would not say. I have been editing these but in the future I will just Dis approve ...they should know better.
I have two comments awaiting approval right now which are perfect.