Great advice for writting the notes down.
You want to "learn" the fretboard, not memorise it.
The fretboard is based on music, so their are basic relationships between notes that when you learn them, they will support other infomation you use and learn.
For example D at the 5th fret means that there has to be a G above it and a A below it, the same relationship as the open strings.
So if there is a G above it then either side of the G is Ab and F#, so that means one tone either side of any G, is an A and a F, the same as there is when a G is played on the 3rd fret E string etc..
All that info, and any more you learn, flashes through your sub-concious in milli seconds in an instant to confirm that you are in-fact playing a D...even the fact that you are on the second fret marker is taken in to confirm you are on a D.
This will happen all over the fretboard if you take the time to learn the relationships rather than memorise notes.
You do not think these things because there is no time.
When you learn, it not only teaches you, it confirms and lets you deduce why you know its a D you have played or will play next.....all the info you have learned is telling you it can only be a D. Intervals, scales, chord tones chromatics etc...if you write the note down and all the notes around it, you learn so much deeper.
If you try and memorise things you have a specific point to learn, so if you forget that specific point you have nothing to refer or relate to in order to remind you of what it is.
If i was to ask you to play the 5th fret note above A...you know what it is before i even finish typing this sentenece, fact is it came straight to you as soon as you read the "above A" part.
