Go Direct
There should rarely be more than three people involved in delivering feedback from one person to another: the giver, the receiver, and (possibly) a trusted third party. Beyond that, problems arise.
Involving more than three people tends to create a “table-shaped” feedback path. This type of feedback gets passed up, over, and back down through bosses and peers. The more people or layers involved, the more delays or distortion.
The best feedback is direct, clear, and timely. A simple “when you did X, I felt Y, and observed Z” formula works well. Separate the behavior from the person. Assume good intent (i.e. round up). And try to give the feedback as soon as possible. I’ve noticed teams who train this muscle tend to take more risks, find more success, and enjoy work more.
In short: go direct. Keep feedback timely and involve the fewest number of people possible. It can take practice, but this type of feedback, eventually, becomes easy to give. Feedback loops complete faster, and, ultimately, comments lead to change.