I've only been reviewing suggested edits for a bit over a month, but in that time, I have never once seen an acceptable edit from an anonymous user. I have had to reject all anonymous edits (almost all as "attempt to reply") because they criticize, change the meaning of the answer, say thanks, or don't help at all.
I understand that Stack Exchange wants to make it possible for anonymous/unregistered people to participate. Considering the width and composition of the unregistered audience of this site, however, it looks like anonymous edits here are more trouble than they're worth. It appears that people with tech problems come sailing in from Google, click around until they find a text field relevant to a particular answer, and dump their thoughts into it without putting any effort or commitment into this community and its policies.
Has anyone seen any good anonymous edits? Is my assessment of their value correct?