reapersaurus said:
i guarantee that humans would have come up with that tactic WAY before the ELVES would in any world.
Why? I don't see elves as mentally inferior to humans. In fact, I see them as far superior (given the same intelligence score) since they have much longer lives in which to learn and synthesize ideas. Most innovation is built on previous work, and typically involves applying several fields of knowledge to a new application. How many different fields of science go into building an airplane or a microprocessor? It requires years of training just to master a single field, much less dozens. Elves are ideally suited to training in multiple fields.
A lot of arguments here have relied on science: crystallization of metals and so forth. One thing to keep in mind here is that this is fantasy and applying physics to it is a dangerous rathole. Sure you can use physics to kill this application, but once you've set the precedent you open the door to using physics to REALLY abuse the system. Saying "no, because of X" implies that it's okay as long as you can find a way around X. Whatever standard you use to defeat this will be the standard the player uses to try again.
I would allow that cast iron is rather brittle for building ships, and that you'll need some bracing to keep it from collapsing, but I don't think I'd press it further.
Some have cited cost and lack of wizards. The whole point of the original report was "train wizards to do this" not hire wizards for money. It costs nothing for a wizard to do this himself.
Also, I thought I read something in there about guns and modern manufacturing? This already sounds like a near-renaissance level setting. Some people have said that you can't do fine detail work at such small size, and that defects will be magnified. That is true to a degree, but OTOH don't underestimate persistence. Look at the miniaturization and precision we are able to achieve in reality! Given that elves are possibly the worlds finest craftsmen, and given the motivation to succeed and restore their race to prominence, I dont' see why they wouldn't practice until they developed the techniques to make this work.
Ultimately, trying to stop this specific spell combo is going to be futile, I think. How many other ways are they to achieve similar effects, and how many other spells and items are waiting to be exploited? Look what you can do with the Create Wondrous Item feat! If you don't want this sort of thing in the campaign, talk to the player or just say the elves aren't interested. I think that invoking physics will only cause problems; if you make it a "human (elf) engineering" problem, you can keep control.
Mike