I have a "Learning Party" question:

[Sove92]

Two tank T9 actually adds more complicated tank mechanics with the tank swaps and all. Or otherwise a tank has to go str gear and become a DPS, which leads you back to the solo tank scenario. And for the PF finding tanks are often the limiting reagent so if you can get by with fewer tanks then it will be less time waiting on the PF.

I was able to tank Nael just fine in STR gear before it got on DF, ate a 2-stack Bahamut's Claw without problems.

with 5 DPS you can get Nael at 46% without she summons the second dragon add. That helps ALOT. And you can push out of phase 1 without too many meteors. Since there is no tank-swap mechanic it's way better to play 5 dps 1 tank.

We did that with 4 DDs before it got on DF, it's really not a problem unless the DPS just plain sucks.

Playing with 2 tanks is far safer for a learning party, at least you have a chance to recover in case the tank dies. If the DPS loss without a 5th DD is so great you can't push below 4 meteors with the current echo, yes, your DPS sucks, bad.