House Republicans forbid scientists from advising EPA on their own research

PrintSmith wrote: I have yet to meet the person who can be said to be the best critic of their own work Dog. That is why one doesn't proofread, or edit, their own work; common mistakes are easily overlooked when one is also responsible for the content.

No, forbidding a member of the board from advising the board on their own work is a responsible policy to follow regardless of what subject the board member is most familiar. We wouldn't let a judge sit on the bench of a trial where he was also an eyewitness, we wouldn't let the judge preside over a trial where he had to make rulings on arguments made by former law partners, or where the judge was originally attached to the firm bringing a civil suit. Conflict of interest applies every bit as much to scientists as it does to every other profession.

According to your convoluted scenario, the "judge" would only be able to testify on hearsay, not on his personal knowledge. Which of course is not allowed. Instead witnesses may only testify based on their personal knowledge and experience.
The Board is not meant to be a "court" where the scientist is being judged, it is a Scientific Board that provides expert advice to the EPA so that EPA can formulate regulations based on the best possible science, which can only come from those with the best expertise on a particular subject matter. Opposing experts can testify on any issues that they may have with the particular expert's advice. That is they way it is supposed to work with science. Each individual provides advise based on their particular expertise and experience, others pick that apart based on their expertise and experience if there are any issues with the advice, instead of denying the best possible advice to be brought forward by those individuals having the best expertise and knowledge. Unless of course, as is the case here, the rules are being rigged to ensure that the best science will not be considered in formulating the regulations.