In my career I have worked on MANY different software applications. Once i got over the panic of joining an established team as well as trying to grok enterprise software in all of it's complexity (see this article), after a few times early on, I realized that there was incredible value-add to coming in cold to a product.
Now, some of you may have your hackles raised right now. When I say 'Software is Software', I mean it in the best possible way.
Allow me to explain
With an established team. everyone know the history and the path that led them to the current product. This is extremely valuable knowledge, and key to the product's success. A new person to the team sees the product without bias or history, and often offers extremely valuable insights and observations as they click through the product.
Consider a new team member as a 'novice/naive user'.
That being said, a great way to both get naive user feedback as well as a product introduction, is to have them perform the same tasks/surveys you use in your user testing sessions.
The new team member will likely ask the same questions that have been asked/answered in the past, but they will also be able to, objectively, see possible gaps in the logic, and be able to offer possible solutions that the team hadn't considered.
We all know how we get;
"Yeah, we can't do 'that' because we don't have the pertinent back-end data from services."
"We tried that 2 releases ago and it 'didn't work'."
"We don't have that capacity based on the SDK."
I think it is really key to re-examine past 'NOs.". Something in the technical foundation could have changed, and opened up new, more robust, features. Maybe the feedback you get could spur wireframes to present to your Sponsor Users and take the product in a completely new and innovative direction.
There is room for both historical and new feedback, both are extremely valuable, and you use them both to make the best possible product!
Non sequitur: I mistakenly gave my dogs cabbage the other day. I wasn't thinking, and shortly thereafter, i wasn't breathing. . . . . .they gassed me out of my office and I had to air out the entire house. Lesson learned (cough, gag, wheeze).