The interplay between Dreadstalkers, demonic cores, and Tyrant clearly demonstrates Blizzard’s lack of understanding of the mechanics and game flow of Demonology.
In non-burst gameplay, it’s cumbersome to obtain rewards from gathering two soul shards through casting Shadow Bolt or Demon Bolt, followed by casting Dreadstalkers, with the anticipation of receiving Demonic Core procs after the Dreadstalkers expire. Over those 12 seconds, many variables can change. Particularly in PvP, where Dreadstalkers are often caught in roots, slows, or other forms of mass crowd control, it would be more practical if the Demonic Cores were granted to the warlock immediately when Dreadstalkers appear.
During our burst phase, the strategy becomes more complex. We aim for enhanced cleave damage from our dreadstalkers, so we boost them with the tyrant during the burst. However, these empowered dreadstalkers only start giving us demonic core procs after 27 seconds: their standard lifespan of 12 seconds plus an extra 15 seconds extended by the tyrant.