Arcane rotation, a more in depth question:

Hi all,

Just a quick one about when you Arcane Power / PoM AB the 2nd time round.

Q. Do you use those above CD's as soon as they are off CD or save them for the next burn phase??? (which is about 40 seconds later)

A. ?
Deleted by Lessismagic
I wait to use AP till the gem is up, which will also coincide with evoc coming off CD as I end that burn phase.

In my mind it is not usually worth it use AP without the gem, one because the SP bump is the difference(for me) of 90k ABs and 110-120 ABs. Also by the time the gem is up evoc should be nearly off CD as I mentioned above.

As for PoM it depends on what is going on honestly. It is nice to use on the AB before you pop AP just because you will get 15% crit chance on that first one, but I use it while moving a lot too.
Wait for gem to be off CD.

Also wait for evo, if necessary. It should have 20-30 seconds left on it's CD depending on your regen and fight mechanics.

When you look at a good WoL report for an arcane mage you should see a large spike at the start of the fight with another large spike every 2 minutes, with a final spike at the end when they are emptying their remaining mana.

In between the spikes it should stay pretty consistent.
The key to burn phase is to stack as much cooldowns on top of each other as possible. You want all the valves wide open for your burn phase, since another 1000 spell power or whatever really isn't going to amount to much during your conserve phase, but it with four stacks of AB it becomes fairly significant.

I think it's important for Arcane mages to have an on-use trinket they can trigger for the burn phase as well, preferably Int or at least spellpower, but anything that increases your DPS on demand that you can sync with Mana Gem and Arcane Power will help a lot. If you've got a trinket or something that increases your Int on demand, remember to use it before you use the Mana Gem, since the increased mana pool means more spell power from the gem. If you're clever with your Incanter's Absorption you can steal another 3000 spell power or so if there's someplace to safely soak a bit of damage right when you pull the trigger.

PoM is really up to you. There are plenty of different ways to use it and they all add to your DPS, so long as you remember to use at least one of 'em. Like Setis posted, using it to trigger your 4th AB right before your use the Super Sayan macro will leave you with a charge of Arcane Potency for that first, most powerful cast. Another option is to use it for the first AB you cast in the ramp up to the burn phase, since that will have the longest cast time and get you ramped up quicker than if you used it on the last. Some players don't use it for attacking at all, and keep it in case they need a new mana gem halfway through the fight, although I think it makes more sense to just make sure you're going into the pull with three charges anyway.

Of course, it can also make sense to save it for the conserve phase or the second half of the burn phase so you have an instant cast in hand if you need to reposition. If you know there's some AoE to be done and something, maybe some *%!! on the ground or whatever, is going to keep you from running in with AE, PoM into Blizzard will proc an awful lot of crits. And finally, one last thing I like to do is Flame Orb into a PoM, and use the Arcane Potency procs on the back to back AM that follow.
The only thing I have to say is that think about each fight and figure out if your burn would be better to use in 10 seconds when you will be doing vastly more damage due to a mechanic or something.