See, I take issue with this. The Adept spell list, by the DMG, is OVERALL lacking in comparisons to a) other casters of its level and b) in overall better power comparison to the Swordsage's capabilities. My point is, Animate Dead shenanigans aside (since it is only a 4th level spell, and thus potentially available in wand form, meaning a properly equipped CW Samurai, or hell a Commoner, with a proper bonus in UMD can duplicate this effect, by the same level). This is actually a fairly significant flaw, as the adept only gets up to 5th level spells, all of which can be produced in wand form, to the same effect as previously stated. Granted you probably cannot beat the adept in terms of versatility of spell selection, but given the preparation we all seem to be assuming, this is a moot point. Therefore, with just that given in the DMG, the adept really only beats the swordsage in two areas: Polymorph and Healing. And as for polymorph, a properly made swordsage can generally out damage whatever the adept's happened to polymorph into. As for healing...well it alone is helpful, but not enough to bump it above the swordsage by any stretch of the imagination. The conclusion? In order to be competitive with the swordsage, the adept does actually need those other (possibly limited) source books. (Eberron, for instance, probably being an entirely different campaign setting) And in this case, they are a bit of a strain on credibility.
I'm glad you take issue with my statements, because I take issue with your statements! Ha ha!
It seems that this has come full circle, because IIRC, when the Monk wanted to use partially charged wands and UMD he was given a mighty gigantic middle finger, but it's A OKAY for Complete Warrior Samurai and Commoner to just jump out from nowhere, WANDS ABLAZIN! I love how you mention "Properly Equipped" like the Adept can't do what they are doing, only, the Adept doesn't have to spend a feat, skill points or points into Charisma just to have the chance to fail to activate a wand and lose a charge. Granted, I understand that once you're very high level you auto-make the check with little difficulty; so what? We're talking primarily about 12th level for this thread.
Somehow, the Complete Warrior Samurai has been summoned into this discussion (along with the Commoner) for what reason(s) I do not know. Neither of them are pertinent to the discussion of the relative strengths and weaknesses of the Swordsage and Adept.
Again, you artificially limit the Adept to core only, while the Swordsage automatically gets core+ToB - or in mathematical terms:
Player 1: Core+Splat
Player 2: Core
Why does Player 1 get a Splat and Player 2 does not? Completely arbitrary. As others have said, all books are available online at a click so there is no real "shortage" of availability in that sense - merely what the DM restricts. It's arbitrary to unequally restrict the Adept and not the Swordsage, especially when the Swordsage is supposedly overall better Tiered than the Adept. If the game was supposedly "Core Only" how could Player 1 "sneak" his character in? So in a fair world, the Adept is getting another book. The Adept is going to get a Domain or Exalted/Corrupt spells or access to Necrotic Cyst or something else making them that much better; to assume otherwise is not only unrealistic but simply unfair DM nerfing/hosing via math.
As you said, you think the Adept trumps the Swordsage in versatility and I think that's very clear and definitely agree. I also think that in the very early levels, and very late levels, a Straight Single Classed Swordsage has an easier time than a Straight Single Classed Adept - but those middle levels are kind of what we're talking about regarding the *specific* level 12 challenges.
I also have said before, and will continue to say, that these non-multiclassed, non-PrC characters don't seem to be very common in any of the games I have played in, seen, or heard about, both on these boards and elsewhere. So the entire situation is a little bit stretched and artificial.