Since no one replied to this, I assume the way I ruled is correct, but I think this is something worth going back to maneuvers and clarify on Thicket of Blades...
I don't think it would, since Thicket says:
Your foes provoke this attack before leaving the area you threaten.
Unless the Crusader had a melee reach longer than 5ft, Charging into his threatened reach does not provoke. Now, if the Warblade charged past him to hit someone else, I'd say Thicket would take precedence due to being a higher level maneuver.
Would anyone object to adding a maneuver level-based or opposed IL-based exception to Thicket?
I'd prefer something like a +/-/default arrangement (which is an absolutely horrible name for what I'm thinking of, but it's all that comes to mind). Unfortunately, its scope requires it to be a systemic change rather than something specific to ToB's maneuvers.
[spoiler]
Basically, any time two absolute statements that are exceptions to the normal rules disagree, whichever applies is based on how many of them are functioning, or the default (normal rules) if there's an equal amount in opposition. Naturally, effects that apply an absolute and specify that they override other absolutes ignore the overridden absolutes when checking this. (Eg: "This damage cannot be prevented by any means, even by resistances or immunities" would not be prevented no matter how many ways you had to be immune or resistant to it.)
In the above case of Thicket vs. No AoO charging (say, War Leader's Charge), there would indeed be an AoO provoked under this system. +1 provoking from Thicket, -1 provoking from the charging maneuver, resulting in the default of AoOs being provoked for leaving a threatened space.
Some other examples:
- Thicket vs. 5 foot step: +1 Thicket, -1 5' step, default is AoO.
- Thicket vs. Boulder Roll + Tumble: +1 Thicket, -1 Boulder Roll, -1 Tumble, so no AoO.
- Thicket vs. Cover or Total Concealment: Cover and Total Concealment don't stop AoOs from being provoked, they just prevent you from taking them. This is already the case according to the wording in the SRD.
And, a few more complicated interactions...
- Thicket w/ spiked chain-style reach + Hold the Line vs. War Leader's Charge: When the charger enters your first threatened space, Thicket is irrelevant (charger isn't leaving a threatened space), so +1 Hold the Line, -1 War Leader's Charge results in the default of no AoO for entering (but not leaving) a threatened space. When the charger enters your second threatened space, both Thicket and Hold the Line apply, so it's +2-1, and an AoO is provoked.
- Thicket w/ normal reach (threatening at 10' but not 5') + Hold the Line vs. War Leader's Charge: As above, no AoO for entering the threatened space at 10', but no AoO either for moving closer since while Thicket counts (leaving a threatened space), Hold the Line doesn't (not entering an area you threaten).
[/spoiler]