You seem to suggest that if you don't put any hammer in a unit for 10 turns, then put hammers in it for 1 turn, then you will be able to not put any hammers in it for 10 turns without losing hammers. I don't think 1 turn of construction resets the timer. I remember trying this once with a building (which has a counter of 50 turns before the decline of hammers starts) and it didn't work.
A good point. Which makes it all the more important to try to time this sort of thing carefully. It's a bit of a trade off--for the cost of a few hammers, you can have a much larger army ready to pop out once you change civics; or you can have a smaller army but play optimally and not waste any hammers.
So I can't "prepare" more than for example one each of Maceman, Catapult and Crossbowman this way in one city? I had been wondering how long these queues are, and apparently they are much shorter than I thought, unless you have a lot of different useful unit types.
That's correct, one Maceman per city. I was pointing out in another thread--I think the current ALC--that the ancient and classical eras aren't very good for this tactic, first because you probably don't have the required civics, and second because there are fewer units to choose from. The Medieval era is great for this because of the variety of units.
I was pointing out in another recent post that this tactic ensures you have a big military since all your cities get devoted to military builds for several turns. And it's a hoot to check the power graph once the builds are complete and imagine the AIs soiling their shorts.
Is there any information how (fast) this deterioration works? Is it a fixed amount or a percentage of hammers?
I'm not sure; I just know it starts happening with units after 10 turns, though I'm not even sure if that's game speed dependent. Someone else want to weigh in here?
Can you overcome the deterioration in the capital by switching
to Bureaucracy? I'd guess production bonuses can't get applied retroactively, but I've seen stranger things in this game.
Well, switching to bureaucracy won't add hammers to those a pre-built unit or building has, but it will add to the hammers going in to complete the build. Then again, to run Bureaucracy, you have to forgo running the +XP granting vassalage civic. I'm usually switching
away from bureaucracy to finish the builds, not to it.
What about upgrades? If you are building a Warrior, have Hunting and hook up cooper, it gets changed to a Spearman. What if the Warrior is queued behind an Archer and a Chariot? I assume it still gets changed to Spearman but the Spearman doesn't get any extra hammers, so while the Warrior was only one turn away from completion, the Spearman won't be, correct?
That's right, though this is another tactic I've used as well. For example, I want a bunch of cannons to be available shortly after I finish researching Steel. Well, there's no point waiting for the tech to finish before getting started. I'll start building Trebuchets in several cities as Steel nears completion, timing the end of the build for the turn Steel finishes or shortly thereafter. The hammers accumulated towards the Trebs are kept and go towards the Cannons. This also works for several other units as well, such as Knights and Cavalry.