ahh, that makes sense. there was an old post on the subject of animation speed, but I haven’t run into any problems with my Builds as far as animation speed is concerned.
these are the 2 posts I found that mention it, by the Mod @Clogon .
the Arcanist & Ascendant Debuffs are different. the Arcanist Damage Debuff is the +20% ED% per enemy debuffed that lasts 0 seconds when affected by Weaken. the Ascendant Arcane Debuff lasts 5 seconds, and this is why it is required for the Arcanist Debuff to last more than 0 seconds.