Just playing it safe and conservative Chris Scott, I'd hate the thought (particularly in a large geometry aircraft) of someone doing a 90 or 180 degree line-up whilst attempting to maintain 10 knots throughout the manoeuvre.
I have no problem with your suggested "slightly less sharp alignment", I do it too, but I've seen a good many trainees shooting for a nice 30 degree flare onto the centre-line, thus using 100 to 200 metres of runway in the process. Not so bad for a JAR certified aircraft which considers line-up allowance, but for a large geometry FAR25 aircraft (which makes no consideration of line-up allowance), you're behind the 8 ball, even if you do it correctly.
Regards,
Old Smokey