I wouldn't say I studied it in depth, but I did study it.
It gets wider and shorter depending on the humidity.
I've seen curly hair made more manageable with a body-wave type perm, which is not anywhere near as damaging as chemical straightening.
I tried a perm once to help manage my curls (Ahem) frizz.
Went for the soft Irish, redhead curls.
Looked good for about a week.
My hair grows remarkably fast.
Had it trimmed at 2 weeks, salvaged it for about another week.
Was so frustrated that I went from hair down the middle of my back to hair about 1 1/2 inches long.
Just cut it all off.