That's the whole concept of it, is it not? Lets take your example and mine. Elemental Bolt Air (yours) and Fire (mine). Using the guideline in the book, which do you think is going to be easier to conceal? One that uses Air as it's source (something that cannot been seen and felt on a lesser impact) or Fire (be the source coming from a torch, camp fire, the feeling of heat in the, albeit small, vicinity). Even if the difference is +/-1 it will still illustrate how Air would be easier to conceal than Fire would be.

It's not something written in stone because it doesn't need to be. This is where GM/Player ingenuity and common sense kick in, where the GM has the final say on what goes down and how. Of which these are applied to both home games and the Living campaign. Be them pre-set or on-the-fly.

Under the right circumstances bonus to "air" and "fire" could be flipped. Say if you were fighting a flesh golem while inside a windmill that was burning down.

I agree that a burst of fire is not concealable in most "ordinary" circumstances - Hey look out, Fireball! But if the object is to cast the spell without it being obvious that YOU cast it, then the elemental choice should be irrelevant.

I don't disagree with this. What I am saying is that every day (different) situations can, and will, affect rolls. You could have 15 ranks in stealth, but if you try to Hide in bright day light, while out in the middle of a flat plain, being merely several feet amongst enemies actively looking for you, while wearing heavy clanky armor, you're going to have a harder time than doing it under more favorable conditions. Granted, you're going to have a less difficult time than say someone with 3 ranks in Stealth, but the penalties will be there regardless. The same is going to go for casting a Fireball vs. an Airball. Fireball is more obvious, and those with higher ranks in stealth will have an easier time to handle the penalty that will might be applied, but the penalties will be there.

Certain spells, from certain sources, under certain circumstances will be easier/harder to cast subtlety than other spells. It's a question of what, when, and how. Just because it's not pressed in ink on paper doesn't mean it should or should not occur.

This I agree with (Emphasis mine). That was not the original statement you made, which I was clarifying.

John

Ultimately, where there are no mechanics to support it, common sense must prevail. We cannot put in mechanics for every single occurrence or situation.

Personally, my take is this: Successfully casting subtly means that no one ties the effect of the spell to you. This is highly useful in situations where the enemies are under orders to kill or have a particular disdain for casters. If you can disguise the fact that you are a caster from a known Harvester or a Ymandragoran thrall, for example, you are less likely to encounter trouble in the future.

Of course, you could solve that problem by actively killing everyone you come across... but that will have its own repercussions.

I appro ... er, *coughs*, Hey! We're heroes 'n' what not!

*hides the slayer dagger*

Tony hit the nail on the head...

it's imposable to develop rules for every situation, and it falls to the Chronicler to make a fair ruling on the fly.