The weirder thing going on is that Highland Bagpipe music isn't played as it is written. Just count up the notes and their value and you will see that there is far too much music written to be played in one measure.
This is because 1. Pipes, being bag blown (you blow into the bag, and the bag winds the drones and chanter) you can't stop each note, or between each note, so three quarter notes would sound as a dotted half note, which really disturbes the swing of most tunes. To work around this, grace notes, short "non counted" notes are played between these three quarter notes, so they will sound distinctly.
and 2. There are lots of these stylized grace notes that are played, each written in a notation that every experienced piper recognises, and sometimes plays in the correct manner. These grace notes are what give pipe tunes their distinctive lilt or bounce, and their lack makes the music seem dull in some hard to define manner. I understand that fiddle music works in a similar manner. Without knowing the shorthand used to denote these grace notes it is impossible to play pipe music as it is written, even if you could get the meter right. This is because the music to these these trills or notes is shorthand for what is to be played, and can't be played as written.
As far as tuning the Highland pipes, first the reed is set into the chanter so that it plays as close to a true octave from the low note at the bottom of the chanter to it's octave at the top of the chanter. By moving the chanter reed in and out very slightly, this can be brought close to optimum. Once this is done the three drones are tuned to a note on the chanter, and of course, each other. The short two sound in unison and the longer one an octave lower, and each is tuned by lengthening or shortening the length of the drone, rather like playing a trombone. This requires the piper sound one note on his chanter and reach back over his shoulder to move the ends of the drones in or out to bring them into tune. There is more than a little vhance of error here, and beginning pipers often ask a more experienced piper to go around and tune the three drones, as this is much faster. Having done all this on one set of pipes, one tries to get the entire band tuned more or less to the same pitch, sometimes truly impossible.
Highland Pipes play a scale nearly unique to themselves, but highland bands can approximate this by playing in the key of "A", if memory serves. In spite of this only the fiddle can accurately match Scottish pipes note for note as they are not fretted, and can play the white notes, the black notes, and in the cracks between these notes.
It is my understanding that Irish or Ullean Pipes, which use a bellows to inflate the bag, and have the drones out the front, are capable of several octaves and are much more easily tuned. I also believe that their tuning more closely approximates a specific key in western music.
Dave