Is it correct to infer that the seperate button macros can each attempt a cast without prohibiting an attempt in the next macro?
Could this be used to create cast priorities?
For example:
Purge > Flame Shock > Lava Burst > Chain Lightning > Lightning Bolt

Code:
//MAIN MACRO - Assuming 4 keypresses per second
/assist focus
/click MultiBarRightButton1
/click MultiBarRightButton2
/click MultiBarRightButton3
/click MultiBarRightButton4
/click MultiBarRightButton5
/use 13
/use 14

//BUTTON1 MACRO	Purge instant	50% of keypresses
/castrandom Purge, 

//BUTTON2 MACRO	Flame Shock instant, 12s duration, 6s cooldown
/castrequence reset=target Flame Shock, Earth Shock

//BUTTON3 MACRO	Lava Burst 2s cast, 8s cooldown
/cast Lava Burst

//BUTTON4 MACRO	Chain Lightning 2s cast, 6s cooldown
/cast Chain Lightning

//BUTTON5 MACRO	Lightning Bolt
/cast Lightning Bolt
Or would I have to use /castsequence or /castrandom in all of the macro's such that
Code:
//MAIN MACRO - Assuming 4 keypresses per second
/assist focus
/click MultiBarRightButton1
/click MultiBarRightButton2
/click MultiBarRightButton3
/click MultiBarRightButton4
/click MultiBarRightButton5
/use 13
/use 14

//BUTTON1 MACRO	Purge instant	50% of keypresses
/castrandom Purge, 

//BUTTON2 MACRO	Flame Shock instant, 12s duration, 6s cooldown
/castsequence reset=target Flame Shock,,,, ,,,, ,,,, ,,,, ,,,, ,,,, ,,,, ,,,, ,,,, ,,,, ,,,, ,,,,

//BUTTON3 MACRO	Lava Burst 2s cast, 8s cooldown
/castsequence reset=target Lava Burst,,,, ,,,, ,,,, ,,,, ,,,, ,,,, ,,,, ,,,,

//BUTTON4 MACRO	Chain Lightning 2s cast, 6s cooldown
/castsequence reset=target Chain Lightning,,,, ,,,, ,,,, ,,,, ,,,, ,,,,

//BUTTON5 MACRO	Lightning Bolt
/cast Lightning Bolt