Mochaccino, I get it done on a regular basis. My natural hair is the most viciously frizzy, unmanageable hair--not just a little wave or curl, but bird's nest frizzy. When we were little girls, my sister (who shares this affliction) and I used to scream and cry when our mother tried to brush or comb our hair and we would hide from her when it was time for a shampoo. As an adult, I spent over an hour EVERY MORNING for about 17 YEARS blow drying it with a big round brush and going over it with a straightening iron, but even that couldn't help when it was terribly humid or rainy. Needless to say, there was no better candidate for thermal reconditioning, and after 17 years, I had had it with the amount of time I was wasting on it and the inconveniences of having to wear a hat in the rain, fog and mist, not being able to go swimming without destroying it, etc. I went to a salon owner who was acknowledged to be one of the top TR specialists in the country, and it STILL went wrong the first time; however, any TR specialist worth their fee should be willing to guarantee their work and fix it free of charge if it goes wrong. This is an extremely expensive process that has to be done routinely--for most people, probably every 4-6 months. So any TR specialist worth his or her salt realizes that TR clients are an investment for them. They should ultimately want you to be happy so you'll keep returning to their salon. I was fortunate. My specialist insisted on fixing the hair (free of charge, of course) and doing it again when it didn't go well, and although those 2 TRs in a row were hard on my hair, it's been responsive to TR ever since. My TR guy even does a free touch-up for me every couple of months to extend the life of the thermal.
And I have to say, as expensive and annoying as it is, it has practically revolutionized my life! I only have to spend 8-10 minutes blow-drying it in the mornings--a little more towards the end of the cycle. Usually I run over it quickly with a flat iron to give it a little more sleek shine and to try to give it a little volume and bounce. That's it. I now have time to exercise in the morning rather than spend a monotonous hour trying to manipulate my hair into something reasonably acceptable for the business world. I know most people would think the cost too obscene, but most people are not afflicted with this kind of hair. I'm thrilled with the results and for me and my life situation, this is a luxury that is worth every penny.
That said, it's not for everyone, and if you're just dealing with a little annoying waviness that can be tamed with a good quality flat iron, it's probably not worth the cost. But if you decide to pursue this again, I would implore you to so some research and seek out a TR specialist in your region who has been doing this for a long time. Ask for a consultation, and go INTERVIEW him or her. Seriously, if you start doing this, you are going to want someone who will work closely with you over the long term to achieve the desired result; otherwise, it won't be worth the investment. And I think everyone's hair responds differently. Some will have great results right off the bat and others will have to work at it with their specialist to get it right.
Hope this is helpful! : )