While using Whisper of Conduction, stasis shards will not begin to track to guardians that are invisible (this can be easily reproduced using Revenant Hunter with Assassin's Cowl). Additionally, shards that begin to track on a guardian who then turns invisible will "track" straight up into the sky, ignoring their previous path. Again, this can be reproduced with Assassin's Cowl. These shards will re-track to the guardian when invisibility is removed, unless they go too high and out of range. While this is pretty narrow, basically only applying specifically to Cowl Revenants or other Stasis users partied with a Nightstalker, it's a huge pain when you're in one of those cases and need your shards for your build.