While many Summoner BiS builds promote Crit and Det, it's strange that SE seems to push Crit/Spell Speed in the BiS weapons.
Since Spell Speed doesn't benefit the DoTs (other than a slight increase to application) and because many of the Summoner skills are instant cast, there doesn't seem to be much benefit to Summoner itself outside of a lowered ReCast time.
Looking at the stats from a pet perspective.
- Spell Speed lowers Recast time of GCD spells including the Pet attacks
- Enhanced Pet Actions when proc'd increases both the Master and the Pets Spell Speed
So by stacking Spell Speed does it decrease a pet's recast time on GCD skills - YES
Can you lock in the increased speed by using Spur while the Spell Speed proc is up. - NO
Can you put your pet into hyper mode if Selene uses Fey Glow while your Spell Speed proc is up and then lock it in using Spur (+50% Spell Speed) - DEFINITELY NOT
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UPDATE
So even though the Enhanced Pet Action when proc'd increases the Masters Spell Speed stat you can't lock the new stats onto the pet using Spur or Re-Summoning.
So BiS gear with Spell Speed
Spell Speed - 458
Crit - 564
DET - 240
Acc - 486
4% chance to get Spell Speed Buff on each attack by the Pet (21% Crit x20% Proc Chance)
So ~25 attacks to proc the Speed Buff (~70 Seconds)
Direct Increase in Pet DPS based on your Spell Speed Stat (about 5% for duration of buff @ 8 seconds)
Spell Speed Proc should drop the pet to a 2.7GCD on their main attack. With BiS Spell Speed (+Buff)
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BiS with Crit/DET
Spell Speed - 430
Crit - 503
DET - 299
Acc - 490
3% chance to get Spell Speed Buff on each attack by the Pet (15% Crit x20% Proc Chance)
So ~33 attacks to proc the Speed Buff (~92 Seconds)
Direct Increase in Pet DPS based on your Spell Speed Stat (about 5% for duration of buff @ 8 seconds)
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ARR 2.2
Comparing the two best gear sets with accuracy capped ~490
564 Crit and 240 DET is equal to 485 Crit and 311 DET - so it might be better to have slightly better chance
to proc the Speed Boost to increase pet DPS.