I totally agree!
I love my Aurifil thread ... but was disappointed with their variegateds as they have that distinct colour switch instead of a nice subtle shading blend from one to the next. The darker section of the thread is the problem, and ends up looking like loose threads are scattered on the quilt top.
I have had one spool of Sulky variegated ... it was much nicer for the colour switching and did not give that look thread look!