So if they could shorten the spell, they might think that the effect would be good. But well, I'm skeptical about how useful spelling shortening can be in wars between nations fighting from a distance.
Even if the chanting time is long, it's best not to use shortcuts because first and foremost is to spread magic with high firepower at the desired location. I explained about it, and after getting the prince to agree, I replied that if he was still interested, I would point it out.
Other than that, I don't feel the need to keep this a secret. As long as you are an adventurer, the opponents you fight are monsters, not interpersonal people. That's why I don't think there's anything to worry about when other adventurers start doing the same.