Is instant cast (0s cast time) possible?

[Builder Bob]

I'm ordering a unit to cast a spell with the following code:

Unit - Order Unit[P] to ( LaserShoot targeting Point) (Before Existing Orders)
Unit - Order Unit[P] to ( LaserShoot targeting Point) (Before Existing Orders)

In another trigger I detect the time between the two casts with:

CheckAbilityCast
    Events
        Unit - Any Unit uses  LaserShoot at Effect3 - Cast stage (Ignore shared abilities)
    Local Variables
    Conditions
    Actions
        Debug - Display ("time = " + (Text((Game play time for player (Owner of (Triggering unit)))) with Any Precision decimal places)) as debug output using Type 1, and Do display it in the game window

The problem is, the time displayed for the two casts are not the same. There's a 0.0625 wait inbetween them. There's also a noticable delay, which is why I went ahead and set up this test.

The ability type is 'Effect - Target' with 'Ability - Arc' set to 360 so the unit doesn't have to turn before casting.

Have anyone been able to make a unit cast multiple spells in repetition without delay?