Different clarification make PoE weird

unique belt Dyadian Dawn says "Ignites you inflict with Attacks deal Damage 35% faster".
Mark explained, ignites deal 35% more fire damage per second and have 26% less duration. The total fire damage inflicted by one instance of ignite remains the same after these adjustments, but the duration is shortened.
it seems less duration is a hidden stat applied because of dot faster mechanism in order to keep the total damage unchanged.

new gem sadism says "Damaging Ailments inflicted with Supported Skills deal damage 79% faster, 80% less Duration of Ailments inflicted with Supported Skills".
its really confusing that this "79% faster" has the hidden less duration? or the "80% less duration" is the only one?

i think PoE mods need unified regulations, badly.