Macro's that are actually useful ?

[Ultimatecalibur]

Any in-battle macros are also going to impede your flow over time as they can't queue like an ability can. Even if it's just to announce you've done something. I can't tell you how often a Provoke macro never actually used Provoke, ending in a very dead other tank.

Most of those failed announcement macros are just badly designed. I've seen to many announcement macros with the call coming before the action which means that another macro can interrupt it (which is what causes the failed use). When they try to use the ability they start spamming the macro which interrupts itself causing it to fail until they stop spamming.