I dono man. I had 23w cfl's only a couple of inches from mine for months and nothing ever happened. At some points the leaves would even get up in between the spirals and I never noticed any issues. Also T-8's for veg that are over driven 70% and I let the taller ones grow right into the tubes to help slow any stretching.

I do know that some cfls get hotter then others but I'd be surprised if that was the culprit. Just my opinion based on my tiny experience and what I've read.

Could it be from nutrient prepared water sitting on the leaves? just a random thought?

I'm having health issues with a few of mine and I cant figure it out so I'm definitely not giving advice on that aspect.