That depends on the fight. On a fairly static fight you can delay your AW for a while until the stars line up in perfect conjuction. But on some fights you can't. Boss mechanics sometimes require you to max out DPS in a limited timeframe that may not allow you to delay AW for much more than a few seconds.

I'm just pointing out that if you have a good 'on use' trinket, it's worthwhile to hang on to it and keep it in your bags even if you get an upgrade random proc trinket. An on demand damageboost is sometimes better than stuff happening at random. When to use the one and when the other, that's also part of the mark of a good ret pally I guess

I still disagree. Proc trinkets tend to have a higher uptime, so you're actually more likely to run into the situation where the on-use trinket is on cooldown when you need it. Or, worse yet, you are saving the effect for the few times you need it, and therefore taking a significant DPS hit. Furthermore, most fights you know in advance when you will need to AW (such as when your guild does heroism/bloodlust, or you can do more DPS to the boss). Sure, there are (extremely limited) cases where an on-use trinket would be superior... such as Twin Valkyr (since you should *only* ever use AW when you have the dark/light infusion). But with proper planning, you can make it so that your procs align with events in the fight that you may need them in. ICD's on trinkets are well known and documented... simply by re-equiping them before you pull, you can trigger their ICD and control WHEN they proc. If you have two proc trinkets with different ICDs, then you do your best to align the more poweful of the two. It really isn't that difficult.

Finally, if you look at ALL on-use trinkets, for their item level they have very weak effects when compared to proc trinkets. This is intentional; being able to extremely easily dictate when your effect goes off comes at a steep price. DM:G is 26 ilvls lower, but it's proc carries more weight. In 2 minutes, DM:G will trigger an average of 2.67 cooldowns at 300 str (600 equiv AP) each for 15s each, while wrathstone only gives 856 AP for 20s every 2 min. That means that for about 40 seconds I could be getting 600 ap, or 20 seconds getting 856 in any given 2 minute window. This is being fair to you, not including the greatly increased benefit we get from strength, as I was trying to demonstrate by ilvl alone how much better proc trinkets are. Furthermore, I'm also ignoring the fact that the static stats on greatness are vastly superior (since that's a function of stat choice, not ilvl spent).

So in response to you pointing out how a "good" on-use trinket is worth holding on to, I counter by saying that any proc trinket even a tier below, assuming it has crit, AP, or STR on it, will outperform any on-use trinket you can find. [Wrathstone] is not even remotely competitive to other trinkets out there... it's good for those who are unlucky and haven't found their second proc trinket yet (Dark Matter, Comet's Trail, or DV), but it is not worth it otherwise.

offtopic.
Is there any site where you can compare dmg with other players from same class on same boss,or it`s only way to browse WoL?

The only place that you can do that currently is WoWMeterOnline.com, but unfortunately it's hosted in either Taiwan or China, and is notoriously slow. Plus, you have to upload your logs to their site as well.

My understanding from what I've read is the trinkets share an ICD, so theoretically you could proc both at the same time if they happen to proc on the same hit after the ICD is up, but the odds of that are very slim. If, however, one procs without the other they both have to wait for the ICD before either can proc again. Can anyone confirm/deny this?

I was testing this yesterday with DMC:Greatness and Pyrite Infuser Equipped vs. Target Dummy. From what I could see, whenever I trinket swapped before engaging the dummy only 1 trinket procced after the 45s ICD, leaving the other unprocced for another ICD (45s). It was generally DMC:Greatness the one that came up first.

Can anyone confirm this please?

The poster you quoted is incorrect. Currently Death's Choices have a different spell ID, so each has its own 45 second ICD, which means you can get a double proc of lots of strength. You can do the equip trick right before starting the encounter to make it proc later if you wish.

Zurm, could you recommend a good addon to track trinket ICDs?

Clcret combined with InteralCooldowns and OmniCC works quite well. Discussion about how to set it up can be found here.

Ex.

Thanks, I'll give that a try.

Edit: Got it set up and it works great. That is exactly what I was looking for. Thanks again.

ForteXorcist also has the option to display internal cooldowns for items (and it has a number of other very useful modules such as general logarithmic cooldown sliders and DoT trackers).

E: Download link