When exactly does an incoming attack take effect? How much time should a player fairly be given to call out his defenses? Specifically, if a spell caster is struck by a packet attack while in the middle of his spell incantation, should he have to immediately stop his spell to call a defense?
There are a few operative rules here to consider.
First, if the target doesn’t hear you, technically by the rules he doesn’t have to take the damage or effect at all. So going by that statement, all those flurries of, “Hold! Ok, did you get my 37 imprisons, 18 dragon’s breaths, and this guy’s 4 assassinates?” shouldn’t be done. If he didn’t act out the effect of the spell, then he didn’t hear you, he shouldn’t take the effect, and you should take your spells/items back.
But we all know the game simply doesn’t work that way. Everyone is just trying to play fair here, so when a hold is called by someone else for whatever reason, we run down a quick check of all the attacks we think the target may not have heard to give them a chance to respond. There’s nothing wrong with that.
The problem lies in the fact that if the target had heard the effect and used a defensive ability, the call for that defense would use up real time. This is a critical dynamic of the game. It takes a discrete amount of time to state the call for an attack, and likewise for a defense call. Monster abilities and gasses consume much less real time to use than spells – that’s one of their primary advantages. Allowing the monsters to call out dozens of defenses during a hold makes them so much more dangerous, because they can continue to blast you with their extremely quick packet attacks or weapon strike abilities without stopping to say “return” or “phase.” Similarly, the verbal calls for cloak and bane were extended for exactly that reason – to increase the real time it takes to use the defense. Individual PCs go down extremely fast to status effects, so it’s absolutely essential that the players be able to interrupt the boss’ stream of attacks by forcing them to call defenses.
That’s also why the “2 second rule” is so important. If you’re hit with an effect while in the middle of a spell incant, you can finish the spell, but you must immediately call a defense before starting any other attack or skill. If you wait too long, you’re supposed to take the damage or effect, even if you had a “dumb” defense ready (like shield magic) or an appropriate cloak. Timing is critical, and those precious seconds when your opponent is essentially stunned because he must call out a defense make the difference between a win and a fail.
The simple answer is, you have 2 seconds to call out a defense when hit with an attack. Unless you have a speech impediment or are purposefully casting slowly, you would always be able to finish your spell before calling a cloak, without disrupting the casting. Calling it beyond those 2 seconds, especially during a hold, shouldn’t be done. If you honestly didn’t hear it, and the PCs tell you what you got hit with during a hold, I’d say you should still be able to use your defensive abilities after the lay-on is called.