first session report
I really don't think breaking out a stopwatch is necessary. What's the appropriate amount of time, and why? There is no constant or correct answer to that question. What you're experiencing is another common dilemma of RPGs, called "meta-gaming". Which is using out-of-character knowledge to influence in-character actions (in this case discussions taking place OOC, that they wouldn't be able to have IC is the same thing).
To some degree, metagaming is of course unavoidable and that's fine and a recognized part of RPing. But metagaming like you're experiencing is not part of that unavoidable part. All you need to do is, once they've gotten to the point where you feel like they've exhausted their OOC time (like just before the plan is starting to come together > ), just butt in and say, "Alright fellas, time to act! Bob, what do you do?", and then go round the table (by Agility score or Logic score or completely arbitrarily if you want). If you get push back, then just explain as I have (and as you've already noted) that they couldn't have this conversation in this situation. But you won't get push back, players just need to be prodded sometimes. To be reminded that this game is about their actions and taking risks, and embracing the unknown consequences, and being a pro-active participant in that dynamic is what's gonna make it fun. Of course, this relies on you as the ZM to make their actions result in dramatic and fun/tense situations and to not always just be ruthlessly realistic and pragmatic (and I'm not saying you did that, just don't punish them all the time for taking risks), but that's a whole 'nother thing.
Edited by emsquared