As a director, I feel one of the hardest things is choosing when to take the scripts out of your actor's hands. I'm not a parent, but I assume this struggle is similar to watching your child try to ride a bike without training wheels. Do you set the date early to force them to get the books out of their hands and therefore get really comfortable early on, or allow them to cling to the safety net until it is necessary to let go.
Option A means some fierce struggle, but in the end a really nice payoff. Option B gives your actors the comfort they need to explore their characters, until they suddenly have only a couple weeks to learn what it is they don't know... and "Oh crap! What do I do with my hands now that they are suddenly unencumbered??"
For this current show the decision was somewhat taken out of my hands - we have a cast member coming in late and I felt it was especially important for the cast to be very secure in their lines by the time our newbie joined us so she can assimilate as quickly and painlessly as possible. I selected a date halfway through the process and mentally braced myself for the idea that this might not be easy.
Tonight, was the first night off-book for Act One. I'm certain it was hell for my actors. All in all, I thought they did quite good. Yes, there were scenes I wanted to allow them to pick up their scripts, but I steeled myself against this with the knowledge that they now know what they don't know.
Did I make the right choice? I guess that still remains to be seen, but for now.. I think yes.