amp input cap for crossover

[pforeman]

I have a vandersteen subwoofer (that I won't be using with my new stereo (full range open baffle with Hframe 18 inch woofer)
The Vandersteen uses a cap at the input of the amp for a high pass cross over 6 dB / octave.
I am planning on a plate amp for the woofer. It will have its own active crossover for the bass (around 200 Hz)
Is there any advantage for the amp It will be (haven't got it started yet) a tubelab simple SE with Kt-88>
Seeing is how this is just a few watts, is there an advantage to the amp or sound to do this kind of cross over over a conventional crossover right on the speaker?
And also, wierd question, could I do this input cap on amp at 200 Hz and add a 6 db crossover on the speaker at this or some other point to effectively make a 12 dB crossover? (if I ended up thinking the 6dB input cap wasn't enough)
Thanks,
Paul