Matt_Stevens said:

jedi, it's because everyone I know gets far more coasters when burning duels vs single layer. Hence the nervousness and intimidation. And heck, some burners just ain't so good at it. A good friend of mine was getting a 35%+ coaster ratio so he replaced his burner and presto, now it's around ten %.

Then get a good burner and buy good blanks, I have yet(knocks on wood) burn a bad BD50, no coasters at all(knocks on wood again) pioneer burner and Verbatim blanks all the way.