Well it's a sure fire way to seal corners combined with silicon and helps with vibration dampening slightly I'd imagine. I've got some 2x4's to screw and a bung load more bracing to do.
I'm keeping the duct tape untill I either brake 150 or give up on this enclosure and go for:
1.) COMPLETELY rectangular Sub Up Port Up
2.) COMPLETELY rectangular sub forward port up
3.) 4th Order Bandpass beast box I designed
4.) 6th Order bandpass enclosure that will almost qualify as wall.
The 6th order modles like a beast. Flat as a board and extends well beyond any sane ported enclosure and is always at least 3dB louder in it's band with and plays a little lower as they both roll off at the same slope. But WinISD is moot so I'll be consulting some bandpass people before attempting it if it comes to that.