First of all, the fret lines on our Steel Guitars are only a reference point for proper intonation for that particular chord or note(s).  Developing your ear is an essential tool for hitting proper intonation when you get to a particular fret line reference.  Now, there is another great tool we have inside us called eye/hand coordination.  When we are only moving the bar a few frets at a time, our peripheral vision sees the fret we are going to move to.  So when you are going to move quite a distance, I like to locate that fret line with my eyes, before I move. So exercising your eye/hand coordination by locating the line first with your eyes is great practice to hit the fret line reference confidently, then using your ear to perfect it.