If this is the case, then I suspect that even a ridiculously broken batman caster won't do a d*** thing to change your DM's mind. Probably the only way to "win" this sort of contest is to out-Warblade the Warblade. What's more, you'll have to do it under the constraints that douglas outlined above.
Of course, one big problem I notice is that even if you do win, you won't be proving that ToB is non-broken, you'll just be proving that casters are broken. You're liable to wind up with ToB and whatever casters and/or tricks you use on the banned list.
About the best solution I can think of is to try to get the DM to let you use ToB for a few sessions as a "trial run", and go easy on the badassery to try to show him that it's possible play a ToB character without destroying the campaign.