you will probably end up finding alot of people with ideas very similar to your own.
For example, in the idea lists, i often get nearly identical idea submissions by totally different people, sometimes weeks or months apart. All you can do, is go with it, and add your input. In the end, if an idea is accepted into the mud, you're not going to get credit for it anyways, other than the personal satisfaction of knowing you assisted in the development of the mud
(and for what its worth, many, many, many people have assisted in the development of the mud)