Any ideas on how to make tactile markers on the neck/fretboard? Or should I just keep practicing intonation to develop better touch? I am of the school that thinks that one should be able to intonate accurately, given enough practice - and hit the pitch perfectly. But, my skill is not there yet, and it seems that my eyesight is failing faster than my intonation is developing. Due to the annoying way my retina periodically detaches, I'm often half-blind, and in low light practically blind as a bat. On two of my fretless ones the fret mark lines do help intonation considerably (whenever playing in good lighting).