to be honest I like to get people on a set of GHBs fairly rapid, blowing steady low A and one drone for a few minutes , normally after 3-6 months chanter practice, the i encourage them to hit the scale on the GHB changing from Blow to Squeeze whilst changing note, it suprising how it re-motivates students after 3-6 months drilling scale and doublings when the blow one note on a set of pipes it can really give fresh motivation at the 3-6 month stage where many students are hacked off with chater practice