I've definitely seen that the Phase 2 status changes have had a staggeringly negative impact on CC/Damage (Damaging Status Effect) builds - to the point of Bleed/Burn setups basically no longer being a viable option in Heroic+.
Which yes, reduces overall build possibilities in Heroic+ content and ruins the fun for those builds. This also makes a hard cutoff for Bleed/Burn builds at Challenging, since they'll take a huge hit the moment they bump up to Heroic.
However - from what I've seen the pure CC Status builds that focus on Disorient, Blind, etc. aren't as impacted at the higher end. Optimized Control builds shouldn't be as impacted by this change as damage status or mid-quality Control builds (again, all this is based on what's been shared with me so far).
That's not to say the change is perfect... but it might be a step in a positive direction to make Heroic+ more demanding of higher-quality builds and more coordinated commun...
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