Thread: Question Regarding Black Mages

So, this week I took into account some tips and really pushed my DPS. Did 335 on T6 and 362 on T8. I'm not even going to start on T7. Anyway, I hear people saying that +1 WD equals + 15 overall DPS. However, this doesn't feel like it when playing Black Mage.
I would say that the +3 (from LVL 100 to 110) has given me about 10-15 extra DPS.
First of all, I don't know if it's true that for other classes +1 WD equals 15 extra DPS.

The only reason I can think of as to why BLM does not benefit as much is the following.
Let's say that +1 WD equals + 20 raw damage (hypothetically). BLM has slow casting times in comparison to let's say a Monk. That's why a MNK would build up way more damage over time seeing that the nature of their attacks is fast paced (also auto attacks).
The BLM has slow casting times and therefore not benefitting as much.
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These are just some thoughts, I'm not entirely sure if it's true at all. Is the extra WD not adjusted to the speed of doing skills?
Thoughts?