Blade Blast detonates Bladefall's lingering blades much faster if initial cast is at edge of blades

Blades on the outer rim of lingering blades take much longer to be detonated when blast is cast towards the centre of the group of blades, when blade blast is cast on the rim, the entire group of lingering blades detonates in under a second

Video:
https://imgur.com/Fbgyojj

Using Spell Cascade and Unleash with 3 seals (45 lingering blades), bug can be reproduced with unleash,spell echo,spell cascade or no support gems, although it is much harder to replicate without spell cascade