Are you talking about compressed springs or cutties? Cut linear springs retain the same spring rate. Are you referring to cut progressive rate springs? If you are, then yes, you will change the average spring rate across the spring depending on which end you cut coils off. But even if you cut the soft end off a progressive, you won't end up with the increase in spring rate that you need to take up the reduced travel.
If you're referring to heat treated, compressed springs, then yes you are right, the spring rate will increase.
My "research" is simple applied high school physics. For which I represented NZ internationally at high school. And I'm not going to list the piles of webpages I read when picking my second set of coilovers, but am happy to direct you to search NASIOC and IWSTI as an excellent starting point. Like you want me to present my research, please feel free to present your own research to the contrary if you think my physics are wrong.
I don't have an issue with lowering springs. In fact, there are some really good lowering springs out there that are well suited to the factory standard shocks. If you want to slam your ride, that's your perogative, just be aware you'll more than likely compromise your ride to do so. But cutties are just dumb. Really plain dumb. I don't see why I'm the villain for pointing that out, or for supporting my arguments with information you could find from any reputable source.
And for bedtime reading, here's a very good thread from NASIOC about what happens when you put a JDM brand name, captive spring with insufficient spring rate / coil length into a standard shock. Enjoy: http://forums.nasioc.com/forums/showthread.php?t=1267918