I can't even say that I need it right now.
You already have an option that lets you pick how many tests to perform simultaneously. Say on my primary backbone, I can handle 32 or 64. However, over one or two slow links, I want to slow that down. Could you add an option (long term) to allow throttling per RMA?
A short term work around, though kludge, would be to set each test up as a dependency on the previous test. This would theoretically run one test at a time.
PS. Thanks for the new RMA tests.