Ok. I don't necessarily believe that people are likely to grow a FULL HEAD of scab hair. After my last relaxer for the most part my new growth felt great-- like healthy hair.
That being said for several months after my last relaxer (seeeeeeeeeeveral months) my front edges would always grow in really weird and, no matter how I pampered them, break off. At first i thought I just had a totally different texture there and I'd just have to learn how to care for it, except as time goes by they've finally started to get longer, and they feel really really different to how they felt those first months.
This was only a small surprise because I knew I had had some fairly bad scalp damage along my edges. My aunt relaxed my hair once and some of that hair didn't grow back for about a year
I definitely agree with the poster above though. I wouldn't start cutting or anything, because it could certainly just be your hair (and as an overall fine haired natural, coarse hair--especially if its consistently coarse unlike this random business I have on my head--can certainly be a gift.)