One thing troubles me a little about some answers above. It shouldn't, in my opinion, be the FT department's job to go into too much detail in suggesting fixes. Inevitably we'll be asked what we think might work, and controlled "suggesting" is entirely in order - but flight testers shouldn't get too deeply into redesign work otherwise we'll subsequently find ourselves in the difficult position of assessing our own design work.
Whatever else I've said previously, it does remain our job to be independent assessors.
G