I've used a 30 plate Duda Diesel chiller for close to two years and never had a clogged chiller. However, I whirlpool and pump wort through the chiller. I even leave pellet hops free and only use a hop bag when I use whole leaf hops.
I recommend recircing through your plate chiller during the last 15 minutes of your boil to santize it properly. Also, using an autosiphon to back flush afteruse is an easy way to clean it, but I will admit that you'll always have some debris in the chiller, no matter how well you clean it.