If you have macros with a relatively short number of commas and can fit 2 into the same macro you can reduce the number of macro spaces required for /click priority listings. I'll use Ualaa's macros for example:

Code:
#show Lightning Bolt
/Cast Elemental Mastery
/Click MultiBarRightButton6
/Click MultiBarRightButton6 Right
/Click MultiBarRightButton7
/Click MultiBarRightButton7 Right
Macro on 6
Code:
/castsequence reset=combat [btn:1] Flame Shock,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
/use 13
/use 14
/castsequence reset=combat [btn:2] Lava Burst,,,,,,,,,,,,,,,
Macro on 7
Code:
/castsequence reset=combat [btn:1] Chain Lightning,,,,,,
/cast [btn:2] Lightning Bolt
Since the macros are processed all at once it still works just like the separate macros, it just saves a bit of space when you are getting near the 32 macro limit.