>>127337791
John Petrucci says he has always needed and still needs to do focused practice and preparation for harder stuff, even the things he has played live countless times.
Let's be honest, dimebag and the likes were more innovators who were lucky to be around at the right time. By todays standards he was neither a very technically proficient, nor a super clean or advanced guitarist. Him being a "legend" rides on Pantera's popularity and the fact that he kicked the bucket early enough to create a myth.
Doesn't mean he was a "bad guitarist", but the hardest stuff he ever played you can now hear from every random dude occupying the amp at your local guitar shop.
Also there is a difference between practice/improvement, and just continuously maintaining what you are comfortable with. There is nothing inherently wrong with the latter. However that is also why you have tens of thousand of guitarists who constantly go "man I've been playing guitar for 15 years and I can't do that!!" because in reality they learned and practiced for a year or two, then never did anything outside their comfort zone ever again.