Advice...

[Silverquick]

EDIT : because it's important ; I failed to pay attention to your last sentence : it is completely false. Like it was in Stormblood, SMN gains a massive bump in potency come the last level.
Indeed, between 72 and 79 it goes like that : Baha trance > Bahamut > Phoenix Trance w/o Phoenix > Repeat.
At 80, you add 5 second to the Phoenix Trance and, well, Phoenix, which is a Baha like.
It would be close from one another if during 72 -> 79, Phoenix trance allowed you to summon Bahamut after it, but it's absolutely not the case. So Phoenix is a complete gain at 80, twice the Demis in the same timespan. More gain than Scorch.

Fair enough,

I will check into it again once I get to 80th in both.
But as of 77th in both in equal gear, my single target damage is indeed higher for RDM.

EDIT: Oh by the way...

In the same time span of 5 seconds, also with the "basic" stuff a smn does :
- 2x200 GCD (ruin 3) = 400
- 5/6 of 2 ticks of both dots so 0.8*2*(50 + 50) = 160
- 5/6 of 2 pet autos so 0.8*2*(80*0.8) = 102

662 in total. So absolute basic spam for both does the same approximately.

I see why you made the mistake though... Your math is actually wrong here.

You forgot to include Ruin 3's recast timer in your calculation... the casting time is 2.5 seconds... and its recast is 2.5 seconds, so its 5 seconds total for the cast. You're in the same boat as RDM there.

You've only got One Ruin 3 in that time, not two... so you have to remove one of your Ruin 3s.

So you're only at 462 total not 662.