*Warning: Opinionated statements below*
I have a lot of interests in bards at the moment, as it's what I'm currently playing in my current group. I've read and gone over the vast majority of linked guides allready, and this seems to be a picky / choosie collection of 'what i want to see' bits.
The guide feels as if It glazes over a lot of RAW - RAI debates in favor of trying to pull a 'one over' on a game breaking mechanic on the DM. ("Maybe I can even go Cleric8 and get Inspire Courage +2.".... "Saner interpretations say this is only from levels, but RAW says 'doubles.'".... etc). Poor form for a guide. Which should be written to encompass suggestions that any reasonable person would deem okay. Outliers (such as implying your cheating via RAW) should just be that. As a matter of personal taste, I would figure out where those 'cheat' spots are and tone them down, or take them out. as it stands, the guide feels a little to machavalian as a whole.
******* Mechanics suggested ******
As a mater of opinion both RAW and RAI agree on this point
First is stacking penalties that, unfortunately, make all the 'simultanious' music applications a moot point. Bardic music gives Moral bonuses. Being of the exact same type means only the highest bonus is applicable.
That said you do have a potential argument that you can have multiple 'flavors' of inspire courage up. Specifically the Dragonfire Inspiration. You you expend a bardic music for the moral bonuses, then expend another kind of music for damage bonuses. Since dragon fire 'consumes' the bonus of whatever inspire courage and makes it into a energy baised damage bonus, it doens't interfear with the first moral bonus. If you have two serperate energy attacks available, those will be additive, not stacking. But to do so would be three rounds (each use of bardic music is a standard action), and three uses. Unless its going to be a very looong fight, or you have time to pre-prep, the value of a third round spent on buffing and rather than batte field controll via spells or other music is debatable.
** Note ** I just re-read what you said. Make the multiple music usage description clearer and more than just a blub when describing / explaining dragonfire inspiration. "...but normally requires another Bardic Music use to activate." Give it it's own paragraph.
Words of Creation feat has a detailed description on bardic music on page 32 of BoED. Both there and P48 say nothing about doubling bonus from any instrument (I have the book in front of me). The Erratta you give is innacuarate. Also, list that Inspire Courage takes 3d4 subdual, and heroics is 18d4 subdual. just mentioning subdual leaves a lot of foot work when guides are needing to help spell out the good combo's and draw backs.
"""Put a thin cord through this horn and hang it from your neck. Nothing in the rules states you must use your hands for this. Hold the horn with enough of your teeth to keep it in your mouth and speak with the rest of your mouth!""" - Would love to see you do this with a 3lb instrument in your mouth. Another 'gag' comment, and you make the joke again somewhere further down as well. meh, not my flavor.
As far as the stacking of items and such, I would suggest you add a blub "Check with your DM if multiple un-named bonus's stack for the purposes of Inspire courage"
It's a legal debate here, but un-named bonus's are just that - labeled as un-named. Meaning that they wouldn't naturally stack (This is RAI talking here). So it's reasonable to assume that you may wanna check before an 8th level bard starts throwing down around +5-8 moral bonuses to attack and damage. Resonably any DM should allow at least a +1 from either an item or the Inspired Perfomrance spell, + one of any of the level emulating skills. This very easily and resonably gives you a +2 boost to your inspire courage without playing the evile schemer or potentially breaking your DM's game.
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Missing components:
If your playing a buffer bard, what else are you going to do while doing your Inspire Courage bit?
Take a look at Melodic Casting. (Complete Mage, p44) which allows you to skip the concentration skill AND cast spells / spell completion / command word while using music ability. This one feat makes you viable to maintain your Inspire courage and still sling spells / scrolls / wands down range (No longer limited to singing and fighting). Singing is best for this, as it keeps your hands free for somantic compotents.
Extraordinary Concentration - Check with your DM first if you can use this to maintain concentration songs (I.E. Countersong) and utilize Melodic Casting. Downside is you still have to invest points in concentration to make it work (making 1/3 of the previous feat moot). If not, a lot of bardic spells / spells from scrolls you can bring do utilize concentration. Still may be a viable grab depending on how multi-tasking you wanna be.
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Spells to optimize or synergize with Inspire Competence:
If your buffing with Inspire competence, and your trying to tell people how to make the best use of it, make sure to mention what does and DOES not stack well with IC / IH. IC is Moral bonus. So spells like bless, Good hope, etc, are slightly redundant. Rage is still a good mutli person buff (affects their str and con, rather than attack and damage directly).
Stuff like that. That way they get the most out of IC and the supporting spells you throw in behind it.
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Okay, sorry for tearing into it a bit, but its a solid start and would love to see this flesh out a bit, and then get streamlined into a great guide.