BRD macro

[Bardo]

/wait 2.5 rounds up to 3 seconds, so over time it'll waste enough half-seconds to be a dps loss.

*edit - Nvm, additional testing, and you are right about this. Decimal points don't work, they just round up or down.

Nonetheless:
The ACTUAL problem with macros, as has been stated several times in this thread is that they disable the Command Queue for actions that are ON the global cooldown.
Why is this a problem?
Because without the server side command queue, you basically have to wait 2x your latency longer to execute an ON global action.

Example of how you can test this:
Write 4 macros identical to this for Straight Shot, Windbite, Venomous Bite, and Heavy Shot.
/ac "Straight Shot" <t>
/ac "Bloodletter" <t>

Then go outside and shoot at something while trying to run through Straight Shot, Windbite, Venomous Bite, Heavy Shot. You will quickly notice that you have to wait until your client updates that the GCD is refreshed before it lets you use the next skill.
Now replace those 4 macros with the skill buttons for Straight Shot, Windbite, Venomous Bite, and Heavy shot. Again, fire them in order and you will notice that you can actually press the button early and it will go off BEFORE the client shows your GCD is actually ready.
This is because of the server side command queue.

If you macro your main ON global cooldown abilities, then you potentially delay your Global Cooldown skills by 2x your latency every single global.
In short fights this won't make much of a difference at all. In 5+ minute long fights, it could mean as much as 10% lower dps even with average latency.