Direct Heat: My hair has not been able to take heat very well.  Blow drying drys out my hair, along with pressing.  If I press it with low heat, my hair will not straighten any more than it would with just a blow dryer, and will revert to tight curls hours later.   If it is pressed at the salon with a free-hand pressing comb, my hair will straighten a bit more but will last one day, or until it gets into contact with humidity or sweat (i.e. dancing).  If pressed using a high temperature (i.e. kitchen stove), my hair will straighten very well and will bounce, blow with the wind, and shine. Afterwards, my hair will tangle and may not revert back to its original curl pattern.

Blow drying only has even damaged the structure of my hair--I learned this early 2003.  When I started taking care of my hair by growing it out and keeping it healthy by using no heat on it, I noticed how much silkier my hair was compared to the damaged half of the hair.   When I styled in twists, the healthy part of the hair (top half) was shinier and smoother than the damaged part of my hair, which looked really frizzy and shine-free.  A head of healthy natural hair looks very different from a head of unhealthy natural hair of the same texture.