Its called constructive criticism, saying all the good parts doesn't help at all. Also i don't see how telling the truth can be harsh, its more harsh to give white lies.

Zackett: Let him state his opinion.
Culapou: If I moved my arms I would have probably lost balance. If I had relaxed any part, it would have flung around. That is why it was stiff. Walking in a straight line to uke? Are you serious? Noticeably, the path was an arch, deviating to the left but heading towards the center when I got to uke.
I do agree with Zackett to an extent. A 6-10 is somewhat harsh. Especially since you don't see walks all that often (Though, they are starting to pop up.) Your ranking of 7.5 would have worked better.