How the hell does that 2's name not get flagged?!
OT: Now the harsh reality, that is if you spec hit/expertise and haste for max dps/threat, you will have survival and mana problems due to using abilities more, you're even aware of this. So my suggestion is (though I doubt you'll care) reforge back some of the haste, if not then SoI is the only thing you can do.
Also you mentioned that you don't use SoI since your healers are pro, does that mean you use SoT since your dps are nubs?
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Seriously though I only played about 25 days tops of MOP and You've had 5 months and... Hahahahahahaha.
I'm very confused why you are using SoT for a 2.5-2.8% dps gain.
I fully understand the whole "every little helps" philosophy, but as a TEAM game, shouldn't you work out what gives the best raid buff?
You could either do 5000 dps with SoT, or you could pull 40k hps with SoI. Sure, your healers are "good" but if you could bring enough healing to reduce their numbers by one, you'd be gaining far more dps for the raid, which would make things die quicker (I mention this, even though it's obvious, because some players feel a 3% personal gain is better than a 3% raid gain).
Blizzard DOES intend you to have mana issues for using the wrong seal, it's punishment for being stupid (like tanking in frost presence).