I use sweep2 but the section don't follow rail lines

I used sweep2, but I don’t know why the section curve don’t follow rail curves and bake model section deform.

frame study 0523.3dm (197.0 KB)
frame study 0523.gh (6.4 KB)

Should you use sweep2? To me, the result of using sweep1 looks better.

frame study 0523_re.gh (7.4 KB)