Out of my 5 Hamer's, 3 have hameritis to some extent. My 97 T-51 is has it the worst, several spots where the fretboard meets the neck. My 2 Hamer's without are my 93 T-62 and 87 chap. Interestingly, neither of these have rosewood boards. Maybe pau ferro and ebony are less vulnerable to this or maybe it's just a coincidence. I too have wondered how this well known problem has continued for so long.