( I split this off into a separate thread because it's doesn't really deal with the student / Sensei interaction )
I think our dojo is formal, but obviously some are more formal than us on some matters.
Was the offense walking behind the Sensei, walking behind the Sensei with a weapon, or walking between the Sensei and shomen?
Just honestly asking so I won't offend others if I visit another dojo.
Many dojo simply have a shomen; some dojo have a kamiza.
Walking between an instructor and a kamiza is a huge faux-pas.
The pattern remains present in dojo that have a shomen that is explictly not a kamiza.
For a fuller explanation of the way space is organized in a traditional dojo and why this might be so, Dave Lowry's article What Puts The Tao in the Dojo
is a good start.