~I was talking to a retired Luther in the pub and got on to talk about fret levelling,  and  he said to me he has seen a lot of  guitars with divots on the 1st and 2nd frets,  and he would sometime try and sand them out  not touching the other frets  and if they got lower than  all the other frets he would replace them if not he would re crown the fret, 
I asked him why not sand all of them to level them out, he said a lot of the time all the other frets where fine and sometimes  hardly used so instead of lowing all the good frets he would rather replace one or two frets and work just on them , After he replace the frets he level them with a file by going along the  fret ,  he said the main thing is making sure  they don’t go lower than the other frets or the good frets , even if they are a little higher probably would be ok as long as strings don’t touch or buzz from the nut . His point was more why waste the good frets by sanding them and also its more easy to replace one or two frets then to level and re crown – polish all the other frets .
Just wondering what people think?  its something to try .
I find it easier to replace and dress 2 or 3 frets than it is to dress a whole fretboard.
Not taking any online orders.
It's routine to replace single frets (particularly in the 1-5 cowboy chord area) if the rest are pretty much unused. Sanding ALL the frets in that case doesn't make sense.