Old WIves' Tale? Rule Book on the Field?

[noobie]

This question is more out of curiosity than anything else.

I keep reading (here and elsewhere) advice to umpires to never bring a rule book onto the field. I think I understand the reasons why we wouldn't want to. But it's an old, old piece of advice -- I remember being told this as early as 1982.

Today, I was reading the OBR (yeah, yeah, I know, different sport), and in its Rule 9.05, GENERAL INSTRUCTIONS TO UMPIRES, it says "Carry your rule book. It is better to hold the game up for ten minutes to decide a knotty problem than to have a game thrown out on protest and replayed."

That statement just makes common sense to me. What's a "knotty problem" depends on our experience level, particularly in one-man ump systems.

I violate the unwritten rule all the time: I pack a current ASA rule book in my bag, but I never whip it out during the course of a game. Fortunately, I've never really had to. But it doesn't take much imagination to conjure up a nightmare where consulting the rule book on the field might make the difference between a protest and not.

I know we have a group of really experienced Blues out there. What say you? (Besides "memorize the rule book"?)

TIA, folks.