why builds about Vaal Rain of Arrows + Mirage Archer

Hello guys,
i keep seeing "Bleed Bow builds " saying that :
" Vaal Rain of Arrows + Mirage Archer is a good combo"

like those :
https://www.poe-vault.com/guides/rain-of-arrows-deadeye-passive-skill-tree-gem-links
or
https://www.poe-vault.com/guides/bleed-based-bow-gladiator-passive-skill-tree-gem-links#comments-paginated


i tried that combo and Vaal Rain of Arrows dont trigger Mirage Archer, according to the tooltip, that's normal, but why those builds say it can ? am i missing something ? :(

Mirage Archer is supporting non-Vaal RoA in that situation.