ziff…yeah I'll post my thoughts on this soon.
Regarding taping straight, I found that my skills in applying the tape precisely improved rapidly as I experimented. My first couple seams weren't that great, but the last few were really good.
It's hard to really describe the technique I've come up with, but I'll try to explain. I don't cut off a big piece of tape. I keep the tape on the roll and unroll it as I go. I keep the roll of tape upright between my knees and then I use both hands to align it. I'm also kneeling on the cuben to hold it in place, and my one hand is also holding the cuben in place and handling the tape. I work slowly (ie. 2 min for a 15" seam) and I press it down very lightly at first so I can still lift it up if I'm not happy. The tape is getting slightly off course I stop, lift the last up the last inch or two and correct it, rather than trying to curve it back onto the correct path.

