Yeah, I'm sure about this. I've seen those guidence notes before and I remember thinking that they should re-write that part because it is misleading.
I've been to see gatwick AMD and I have it in writing that should I will get a class 1 after LASIK if it goes ok. My astigmatism is -3.5 which is .5 over the renewal limit and 1.5 over the initial limit.
Hope that helps - I think you should speak to Gatwick AMD.
Get LOTS of qualified advice before having refractive surgery and don't expect the CAA to encourage you.
I hope this is good news and good luck.