I recently had a question from students in a referee training class asking if someone chose "defer" what would the next step be.
Students had two different responses and each with a good argument for his/her rationale of either:
1) team A says defer, team B gets both choices ie end to start and choice if will serve or receive
2) team A says defer, team B chooses either end or to serve/receive, then choice returns to team A for final decision of remaining choice. (adding time to decision/choice pre game briefing w/referee or in recreation play)
As defer is not used often do we need to keep it as the writer is recommending.....although if decided to keep defer as an option will recommend also indicating in rule book and certainly in officiating handbook the consensus and best practice for a team's choice after opposing team choses defer.