I just wanted to share this rules update as well as a note for myself as an L1 regarding the effect of the new card previews from Eldritch Moon, Emrakul, the Promised End and Coax from the Blind Eternities. The new ruling is: You can now never see an opponent’s sideboard, even if you control that opponent. The exact language of the rule is still being finalized.

The changes were done as the old rule has made huge ramifications at every level of tournament play. It brings up questions of informational access, lengthy note-taking delays, the timing of strategic concessions, team dynamics, even the physical interactions between players.

This will take effect and implemented I think during the Prerelease of Eldritch Moon. Any updates that will be posted from Magic Judges or any other legit platform will be reiterated here.