Yup… Can confirm this is completely unusable in PvP.
Been dueling a Warrior repeatedly just to test it with auto swings. If you dont FD at the perfect moment they still hit you and keep you in combat. Equally, if your pet has hit or been hit in the last 1.5-2.5sec (seriously wtf with the delay on EVERYTHING in Classic?) you can FD… your trap is highlighted… however it will NOT drop a trap during that time.
This has made PvPing vs Rogues and Warriors completely and utterly pointless as we have ZERO way to disengage and get range. I never played Legion, BFA, and majority of WOD… however I can say this has and was never an issue with my Hunter since 2005.
Get this bogus #@$% garbage retail Legion FD @!#$ out of Classic… Private servers actually did the FD/Trap better than Blizzard, and that says a whole damn lot.