Iv been wondering about this since the release of Hero's of Abyssea. Finally getting around to mentioning it.
Why do atmas such as Atma of the Earth Wyrm (Gain full benefit of Earthsday/earth weather bonuses) and Atma of the Scarlet Wing (Gain full benefit of Windsday/wind weather bonuses) effect everything except trial weapons?
By the atmas definition it should count for ToM. I was quite excited for these atmas the very first time i saw them, because i thought how great they work together with ToM weapons. I was highly disappointed when i found out they didn't help.
And the thing about it is, it wouldn't make things 'easier'. You can still do trials in Aby on specific elemental days. This only increases how often you can do it. So it wont make it easier, only make it take less time. Similar to the adjustment making dyna once a day.
And theirs an atma for each element. So how about allowing us to actually use them for something important? (granted I'm done all my trials weapons, but id still like to see it)