I understand the idea of the "haste cap" is that we don't want to waste stat points on haste that would waste effort trying to push the GCD below the limit of 1s. What I don't get are the numbers. Using the formulas on wowwiki and EJ, I would need 50% haste to push the GCD from 1.5s down to the limit of 1s, effectively hitting the "cap".
Borrowed Time: 25%
TOTAL: 50% CAP
19% haste at 32.79 rating per percent increase (level 80) would take 623 Haste Rating.
Tracking the GCD exactly is kind of tough, but I believe flash heal is affected by haste the same way, and I'm getting 1.0 second flash heals with only about 270 haste. By my calculations I should be getting 1.16 second flash heals and GCD, but it looks like I'm already at the cap. Is there some factor I'm missing, or is flash heal affected by something extra and I'm not at GCD cap yet?
On a side note, is it possible to push flash heal below 1s? GCD would prevent another cast right away, but would it be a possible means to increase reaction time or are spellcasts capped too?