Let's all get something perfectly straight, the ONLY way there could be more or less flats attributed to tubulars is pinch flats and ONLY pinch flats. Based on rim design, tubulars are less likely to get pinch flats.
Flats due to road debry is mostly attributed to tire compound. You can buy BOTH tubulars and clinchers in compounds for flat resistence or other attributes that float your boat. But to say you get more flats on a particular tire because "you" got more flats on a particular tire is just plain silly.
And for the record, in the last 5 years I have had 1 flat on tubulars in 15-20K miles and 1 flat on clinchers in 5-8K miles of riding. Both due to the fact I rode them to thread bare and was too cheap to change them earlier.