After I read RUFHAUS 8's and YCHTT's answers, I have checked in the rule book :
http://www.diplomacy-archive.com/resources/rulebooks/1992AH3rd.pdf
It indeed stipulates that no communication should happen during the retreats and builds phases and that these orders should be written immediately, but it does NOT stipulate that these orders should be played immediately :
• "The retreats are written down immediately by the players concerned, without diplomacy, and simultaneously exposed as with movement orders." (Rule XII, page 5)
• "As with retreats, builds and removals (collectively known as "adjustments") are written and exposed simultaneously without any preceeding diplomacy." (Rule XIV, page 6)
So, even if it is true that the rulebook stipulates that retreats and builds orders should be *written* immediately, the rulebook does NOT stipulate that these orders should be *played* immediately nor that the game should be sped up at that time.
Even though the phenomenon described by RUFFHAUS 8 of losing players stalling uselessly the game indeed exists, it is another question completely unrelated with rulebook press.
As a conclusion, in rulebook games :
• disabling private press during retreats and builds phases satisfies the rule that prohibits communication at those times ;
• the rule book does NOT stipulate that retreats and builds orders should be played immediately ; what's more, forcing the readying of orders does NOT even force these orders to be played immediately ! Indeed, players can wait the full length phase before entering their orders.
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@ RUFFHAUS 8 and YCHTT :
You can certainly understand my position since it was yours when the question of rulebook press was first brought here :
https://vdiplomacy.net/forum.php?viewthread=68430#68430
In that conversation,
• YCHHT wrote, on February 23 2017 :
"I can agree with no press, but not the "saved auto readies". Saving is like writing it on the paper. Readying up is like dropping it in the box."
• RUFFHAUS 8 wrote, on February 23 2017 :
"The saved button offers players a chance to do a quality assurance check on the orders that they have entered, something made very effective by using the "show server side stored orders for this turn" feature. This gives you a graphic representation of what ordered the system is recognizing. For that reason I like the save button, but it works best when players ready up after checking them. I'm not sure that works with your suggestion, but from past experience the QA check using saved orders and the map graphic has saved me dozens if not hundreds of mistakes."