I don't understand really. With Marduk you'd also gain +3 MND and -3 enmity in addition to what you listed, and +7 Divine skill. Goliard is ok, it has one more MND and one more -enmity, but less MP and no Divine Skill. They're actually fairly similar pieces. I don't know why anyone would wear Goliard over Marduk's Tiara though unless you were a Taru.
Mostly because I have other macro pieces for the same purposes. The headpiece for me is the first piece to get macro'd out in favor of stat gear. All I do is cast one or two spells, usually a regen, a haste, or a protectra, and then depending on the fight and the next spell I'm casting, I'll go to one of my other pieces. It's a good piece, but it doesn't have the most/best of any one stat except divine skill, and I did say it's a good macro piece for repose and banishes/flash. It doesn't even have the best mnd/enmity down balance -- that's a toss-up between the yigit turban and the goliard chapeau. I would just personally rather have MND+4 and enmity -5 at the cost of assault points and one more inventory slot over MND+3 and enmity -3 at a price tag of ~2m, plus the time/effort of getting the requisite pieces in salvage. I just don't feel it's worth the time, effort, and money when the only stat it really has over anything else is the 2/3 additional divine skill over an elite beret (+1), and depending on the rest of your divine skill gear, that +7 might not even push you up to that next tier of effectiveness. Especially if you don't have another job that can utilize the piece. I have BRD, and this piece plus oracle's pigaches will move me up a tier in my march. As soon as I get the 25, I'll put the money into upgrading this piece, but it's taken me months to get to this stage because of bad luck on drop rates. I can't imagine anyone putting in this much work and money for a piece that's inferior to a simple combination of a couple of other pieces.
I didn't intend to compare tiara to goliard, just saying it's a nice piece in general. I'd be more inclined to compare yigit to goliard if I were deciding on just one piece to use. Nearly the same MND/enm ratio, with goliard having the added benefit of some HP/MP while idling (just in case you're in one of those really good parties getting 8-9/tic refresh between your BRD, your COR, your gear and your sanction [if applicable]) and more hmp. Those two are comparable. I would say marduk's tiara lends itself more to a faerie hairpin/elite beret/yigit or goliard combo. Added benefits of slightly more divine skill, a couple more inventory slots in your bag, and no HP penalty at the cost of slightly less mp, the possibility of that extra divine skill going to waste if it doesn't bump you up a tier, and the actual price tag.
That being said, this is just my personal feeling about what I would use on my own character. I'm not denying it's a good piece, because it is very nice. It just might be a little bit nicer for people who are using different gear swaps, people who can't afford to or don't prefer to sacrifice a little HP, etc. I'm really not too crazy about middle-of-the-road gear, which this seems to be. Yeah, it's good to cut down on inventory space, but you do sacrifice a little bit in all areas except divine skill. I'll take the hit to the inventory to get that extra couple of points of MND, that extra -enmity, or that extra +15 MP and not worry about it. I knew when I decided to level WHM as an elvaan that I was going to have to work harder and use my gear as intelligently as I could to keep myself ahead of some other races who are naturally better suited, so I'm not really afraid of going 65/70 into any situation. For me, it's a matter of optimizing performance before inventory. Edited, Nov 4th 2008 11:33am by lauplebaud