No, not exactly. I call the differences improvisation and variation.
I love (most) jazz for it’s improvisation, and I love Irish music for it’s variation. Some jazz will actually work on the whistle and pipes (you need keys for jazz on pipes), but I have tried some that I can’t find anything that “fits” in jazz.
Jazz-like improvisation is based on the chord progression of the tune whereas Irish music uses variations which are based on the “bare bones” of the melody.
The general rules I use to “fill out” a tune and make it my own go something like this:
I like to cut, double cut, or yelp the downbeat note (e, f, and g of the second octave for yelps) in order to emphasize the downbeat.
For a dotted quarter note, I substitute a roll, or use a run with the note, a note above or below that note, then the note again, splitting the note into 3, perhaps holding the note for the dotted quarter time if it is one of the “special” notes of the chanter, such as C natural or bottom hard D. Suprise the listener by doing something differently each turn.
For a quarter note, I tend to cut or use a short roll for variety.
For a 3 note run, I like to invert the run or substitute a roll on the first or third notes of the run.
Play around with these until something “sounds right” or suprise the listener. Try to do something differently each turn.
As others have said, other instruments can give you hints. Mary Bergin’s tinwhistle albums are crammed with variations and I got lots of mine from her playing.
Variations were one of the things that first drew me to Irish music, then I heard Willy Clancey on an album I had bought for the whistle tunes and I got hooked on the Irish Octopus… 