APM is also fight specific. A fight with a relatively high amount of downtime is going to have lower APM across all jobs. You also see a rise in APM with gear, as you can eat mechanics that you're not really supposed to for extra uptime.

You're much better off looking at relative APM values between two jobs (such as NIN) in the same fight than you are comparing the same job on different fights. If NIN APM is 40, then you're probably not going to be playing at a higher APM.

It's pretty clear that DRK and GNB are the faster tanks in this expansion. The difference is that GNB follows a rigid rotation much like PLD and doesn't have any real resource management, while DRK is much more fluid and punishes you for not being at correct thresholds at correct times. LS appears to be particularly important to get out as soon as you can, as it looks like it accounts for around 10% of our dps.