Jeskai Energy runs a full suite of countermagic (Consign to Memory, Spell Snare, No More Lies) and removal (Galvanic Discharge, Wrath of the Skies), making Veil of Summer excellent to make our spells uncounterable on the turn we need to resolve our enchantment. Unholy Heat cheaply answers Ragavan, Nimble Pilferer or Phelia, Exuberant Shepherd before they generate value, and since our graveyard rarely gets large here it will usually just be dealing 2. We trim slow, non-interactive cards to make room for protection and removal against their tempo-oriented shell.