Nemmish, lol man, you are such a pain XD on 25-men raids a good disco priest uses PW:S, PoM and Penance 98% of the time. and you are arguing what the other 2% should be? its damn near irrelevant, really. but you came here fighting like you are on a holy crusade or something. the girl is in bis gear and youre SHOUTING about +20 spirit on legs and a +23 sp gem on gloves, thinking it would change how the world turns. really? :D
youre concerns are mostly about mana management. cant you imagine that she managed to learn how to control her mana over that 5 years of playing as a disco priest? btw you overestimate the importance of spirit. for a disco priest max mana is more important than spirit or mp5. Rapture, Hymn of Hope, Shadowfiend, Replenishment, Mana Tide Totem, these are your main source of mana and they have nothing to do with regen. im not saying that spirit is useless, but intellect is a better choice when it comes to manareg, and it gives you some extra crit chance too.
about crit vs haste. as i mentioned in 25-men content as a good disco you will barely use anything but PW:S, PoM, Penance. and 2 of them are instant spells. now, with only 11% haste from gear you become GCD capped ( 11(from gear) + 5(from Wrath of Air Totem) + 3(from Boomkin or Retri Pally) + 6(from Enlightenment) + 25(from Borrowed Time) = 50(this caps the GCD at 1 sec) so gathering more than that will give you almost nothing. stacking crit after you reached that 11% haste on the other hand will give you more and more bubbles from Divine Aegis.
tho in a 10-men environment haste will become a bit more important since you wont always get those hastening buffs from the raid members. and you will also rely on PoH (and in some really rare cases using GH can also be a good ide), and the faster it is the better.
she mentioned that she uses PoH surprisingly often. in that case the Holy Reach talent is a must. i dunno if you are familiar with the basic mathematics from elementary school or not, but if you increase a circles radius with 20% it will increase the area of the circle by 44%. it is a priceless talent if the group is spread out (and mostly it is) and some huge aoe damage is happening. and any time a disco uses PoH that also means at least 2 bubbles from DA.
the usefulness of Improved Flash Heal is near zero on 25-man raids. on 10-mans tho, you should take in consideration the following things:
-do you have serious problem with mana management, and if you do is it because of FH spam?
-how often does it happen that someone is under 50% hp, has Weakened Soul debuff, your Penance is on cd and you have the chance to heal that target with a FH before the other heal(s) heal him/her above 50%?
this talent is far less useful than you would think if you and the other healers are in good gear.
Nemmish, if you think that your healing method and gearing strategy is the one and only way to be a good disco priest, then you are an arrogant *****.