IMO, the reason Fistweaving will do better in DF is not because of Faeline but because of other talents:
- Focused Thunder (2 charges of TFT, normally was mutually exclusive with Rising Mist but now can have both)
- Rapid Diffusion (RSK and EM proc a 6s Renewing Mist)
- Misty Peaks (10% chance to get a 2/3s EM when Renewing Mist heals.)
- Gift of the Celestials (1 min cooldown for Chi-Ji but 12s duration)
- Dancing Mists (Renewing Mists has 10% to spread when going to a new target)
So with those talents you can ramp pretty heavily by casting both your RM charges, Faeline/EF as usual, then TFT and triple RSK, then cast another RM if you want as the cooldown will be done by then.
Now you have 5-6 RMs on the field (overall durations 32s/32s/12s/10s/6s/20s in order of generation), which can cause fun especially with Misty Peaks (10% chance for RM to proc 2-3s EM) and Overflowing Mists (damage for targets with EM heals for 2% max health), and those mists can proliferate into more mists even before you further extend them.
You can repeat this effectively every 30 seconds, maybe less depending on Font of Life TFT cooldown reduction proc rate.
But if you really want to ramp for a raid, then you can use Chi-ji every minute to get out 2-3 EMs effectively free, which get out 2-3 more RMs too.
And the instant Vivify allows for a quick big cleave while still Fistweaving.
Meanwhile, casting Mistweavers get…Unison.
I haven’t tested most of these things but the theorycrafting is fun.