I agree with Debbie to a point. Line edits can be redundant for all the reasons she states, but at the same time if reasoning is offered, it can help a poet see a new way forward: consistency in word usage and syntax for example. Full re writes also have value as they can illustrate by example how the same may be said differently or offer insight into how what is there is understood by the reader.
I feel that there is only value in a critique circle when there is mutual respect. Respect from critter to poet, and vice-versa, regardless the skill level of either, or whether there is full agreement from either side on the information provided or its format. Appreciation and honesty follow very closely afterwards.
The one problem that arises is the incestuous nature and how that can drive commonality between works and lead to inherent stylistics; new blood mitigates this, so respect should also equate to welcoming newcomers in a way which doesn't leave them excluded or cause conflict. However, it is still normal for personalities clash, that shouldn't effect the content of critique, the receipt of it nor view of the poem.
I consider it an honour to be allowed to act as one of the first set of eyes on a work, and take that very seriously. I critique openly and with pride and enjoy seeing a work develop, and how that carries over into later pieces... I also learn and grow simply being part of that.