Dyeing and Plying

I don't quite understand different techniques of spinning hand dyed roving.  I find spinning roving that is 1 color rather monotonous.  However, I don't really like the barber pole effect of dyed roving that is then spun and plied.  After reading this article, I decided to try and apply her techniques.
There were two issues.  She talks about the different techniques of pre drafting versus splitting/ stripping, yet in her experiment, she plied one with a white yarn and plied the other with itself.  I really couldn't tell the difference, and the fact that she therefore had 2 variables bothered me.
I took this roving and split it, plying it with itself:

 And the result: 

Then I took this roving and pre drafted it and plyed it with itself:

 

I couldn't tell any difference between the two techniques.  

So I decided to run an experiment of my own.  I dyed up some roving with koolaid in my crock pot (lemonade, black cherry, and iced blue lemonade) ( I think).

The resulting roving looked surprisingly like a snow cone.  

The pre drafted roving (top) had a much greater chance of multi colored singles.  The stripped roving is a little more vibrant.  In both of these, I divided the roving in half, spun on different bobbins, and then plied together.  There wasn't a large degree of matching up.  I still can't tell much of a difference between the two.