I have spent hours tracking down why something exists as it does within a company POM. On multiple occasions.
All because there is no obvious documentation for things like dependencies. Yes, we could use XML comments but these will not show in the results of any documentation tools.
What I am asking for is a <comment> element to be permitted within a <dependency>, <exclusion>, and probably a few other areas but those are real immediate areas of need.
This was discussed briefly on the -users mailing list many months ago and was generally met with approval. I can't remember adding it here though...