There seems to be just this whole idea of dipping into the monk with other classes for the feats, saves, and air stance is going around for every class under the sun. Is it really viable for a FvS at all?
Just far looking at the classes I don't think so, let me know where I'm off and anything I missed. I'd like to hear of some good counter points.
Wisdom to AC
Consider this +5 Mithral Full-Plate gives +13 AC and is medium armor making a FvS profecent in it. Comparably with +6 bracers you need a total of 24 wisdom to equal that and you won't achieve it until much later in the game as opposed to sporting +5 armor by the 8th level. In order you get 24 wisdom you'll have to sink a lot of your starting points and/or level up points into it. Which means you'll lose out in str/con of a nonwisdom dedicated build. Also I hear AC is pretty worthless at epic, dunno for sure on that.
Since wisdom effects the DCs of offensive spells most FVS will have a lot of it, even on a melee based build. My FVS is sitting at 32 Wisdom right now with items. You would likely be wearing DT, which has +6 armor and Chaosgarde bracers (or +8 armor bracers, why would anyone only wear +6 armor bracers?) Also most melee based builds are going to be TWF builds (except WF) which means they will have higher Dex numbers to up their AC as well. It is true that the AC you can obtain on a FVS probably isn't going to do anything for you in epics, but it certainly helps while leveling up.
Evasion
I still don't understand why someone would chase after this. For the most part it's to cover your rear when you run though traps, play smart and get a rogue in the party. Problem solved. Against spells, well there isn't that much going for it. For three different energy types anything less than 80 damage isn't going to hurt you which I think means dodge the dragon's mouth and you won't miss a thing. Or is there a lot of stuff to evade at the end game I haven't heard of yet?
Evasion is amazing and probably the biggest reason to splash monk. It is not just about avoiding traps. There are many spells that have reflex saves associated with them too and FVS have very good saves in general to make evasion worth while. Being an evasion healer for enter the kobold? Awesome. Not getting hit by a single fire ball while on the bases in Epic Von6? Awesome. Only having to deal with the bludgeon damage from meteor-swarms that Harry is so fond of casting? Awesome. Those are just a few examples.
Air Stance
Gives a +10% to melee speed. Going off the AC is worthless part, just get armor/decent of Melee Alacrity which also has +10% attack speed. Said prop is available though rare loot, greensteel items and probably has a chance to spawn out normally. You can pick up the Air Stance at the 1st level given you a speed boost much sooner in the game than chasing over the enchanted armor so I guess thats pretty useful, reincarnate later on to drop the monk level.
No FVS is splashing monk for wind stance. You can't use stances with non monk weapons.
Aligning the Heavens
I'm too lazy to run the numbers here, and they are probably too complex to really figure out but if you med before buffing, which no party lets you do and I've made it though 12 levels as my monk, you'll have a -25% factor in SP costs, you can pop off the boost pretty much are the end of each encounter to heal everyone up too but don't expect to have it while you're doing things like blade barrier and divine power.
Compare to the almost 400sp lost from not taking two levels in FvS, the bonus dilution so you only get +90%sp from items, and the chances you'll just have someone that dipped into or is a monk in the party or raid.
Most monk splash builds have 2 monk, they can't cast aligning. No one is splashing monk for this either.
Feats
This is probably the main reason I suppose. Everyone loves extra feats, but is it worth the dip?
You'll want Empower Spell, Maximize Spell, Quicken Spell for spellcasting, Power Attack & Improved Critical for damage. From there normally you'll have two feat slots.
Extend is a good pick at low levels, but later on it really doesn't seem all that useful other than extending Divine Power. Toughness is another good pick but with Death Pact's auto res, Stalwart Pact's +100 temp HP when you lose enough life, Divine Power giving you temp HP every time you cast it (which is every 2~4 minutes), being able to pop off a quickened +240hp (mass) Heal spell off, and in the case of ditching wisdom for str or con it doesn't seem absolutely required either though probably highly useful, I mean what else are you going to take?
Two extra feats is nothing to sneeze at and I think you are underestimating toughness. You can get so many extra hit points from having toughness through enhancements. As a melee FVS, which are the ones typically splashing monk, you are also going to want the entire TWF line (WF is the exception though I assume they want the TWF line). A FVS without a monk splash will not have enough feats for that.
Damage
Monk's lose focus when you use nonmonk weapons, so you can't use any of your FvS's faith weapons or the whole wis to ac & combos are shot out the window. Outside of the dagger all monk weapons have a crit range of 20 and only the staff can be used two handed.
Wis to AC stays even with being uncentered you just have to be unarmored. Virtually NO monk splash FVS are using monk weapons (which, btw, the dagger is not).
A glance at the thread
New to FVS: Is this feasible? and currently the bottem post says it will have 16 str by the 20th level and even plans to have ITWF & PA so I'll use that as my example since it's both TWF and monk based. With +6 enchantment after that it has what I fathom to be the damage of 20 per hit or 23 with a strike. Thats 1d6 for fist/kama + 5 (enchant) + 6 (24 str) + 5 (PA) + 3.4 (1d6 dmg strike), avg 23 with a crit range of 19~20. Where as a scimitar user takes advantage of FvS's +2 damage and sports a 15~20 crit range, or a warforged who gets an increase his str damage by 50% and getting +16 off his power attack and a 17~20 crit range. It seems even offense takes a huge loss.
Again, FVS monk splash builds are NOT using monk weapons.
Spells
You give up two 9th level spells and one 8th level spell known to dip into monk for two levels. This pins you to a single 9th level spell where as I plan to take Mass Heal to heal the entire party at once for a large amount, Energy Drain becuase after empower/maximize anything not immune to negative energy is going to suck afterwards, and True Resurrection since people will probably just redie if I use anything less and I won't have to waste time healing after they res.
Which ones will the monk dipper give up hmm?
This is about your only valid point so far. It is a little frustrating to give up so many 9th level spells. I took Mass Heal. Resurrection by itself is usually enough and other casters are usually so level drain happy so they can insta kill mobs that it's really not necessary for me to be.
Damage Reduction
Last thing I'll touch on. Pure FvS get DR 10 / some metal. Suddenly you take less damage from pretty much everything and probably ignore the TWF monks in pvp since they only deal half damage to you. Really, 10 may not be much if you're getting hit for 150, but from what I've been killed by in the Vale's explorer area the DR 10 will make a huge impact in how far I get to run away (only 14th level so far).
Stoneskin gives you the same DR, and since a lot of melee FVS builds count on having 2 MinII weapons you'll have quite a few clickies. I also have the guard that procs stoneskin on my DT
My view is biaist towards pure FvS based on the above reasons, am I in need of enlightenment?
Yes you are iin need of enlightenment. Hopefully my answers helped 