Imagine that you are making a 7'6" (or 90") rod. Your across-the-flats measurement at 75" might be .285", and your measurement at 80" might be .315". That's a jump of .030" in just one five inch station, and not what I would consider a swelled butt. However if your measurement at 80" were .365", that's an increase of .080" over just one five inch station... and would like be considered a swelled butt. That's quite possible with regular forms, and both looks nice and makes the rod feel different.
Thanks for this. It's something I've always sort of thought about but never really pursued since my 1st rod is still on paper...(shhhh...)
Anyway, I have this thing for the looks of a swell. I just love them. Always have. The function/modifications to the rod action notwithstanding, I could see me altering a few given tapers to include a gentle, not steep swell. It's just me...I really like the look and I'm not that good of a caster to quibble over a slight casting feel.
Thanks for this young fellah! Hope to run into you one fine day!