Could you please suggest a good paper on this, as an example of the technique you are questioning?

There is no clear evidence.

As simple as that!

Ablating the singularity point, which is the center of the reentrant arrhythmia (i.e., center of the tornado), may terminate the reentrant activity and thus atrial fibrillation. After circumferential ablation of the pulmonary veins and posterior wall of the atria, many EP labs employ dominant frequency mapping to localize the region of highest frequency activity,. Many argue this region is the driver of the arrhythmia. If this driver is a reentrant arrhythmia then ablating the singularity point has a high probability of terminating the arrhythmia. Please recognize this is a highly debated area of research.

dear  David S Auerbach

Precisely. If the singularity point is the centre of a reentrant arrhythmia, then the path is around it, and not through it. I would argue that the strategy should be ablating a line that cuts the path of the reentrant arrhythmia. Things are particularly interesting when the path is through a 'channel' between 2 points of singularity with opposite chirality. My group will be doing more theoretical and practical work on that. Watch this page...

To be more precise the singularity point is where all of the phases of the action potential converge. The path is not around the singularity point.  The trajectory of the singularity point is what creates the core of the reentrant activity  Yes, your linear ablation would apply for figure-of-eight reentry.  

Dear Dr. Auerbach. As you very well say : Please recognize this is a highly debated area of research.

Therefore, there is no clear and indisputable evidence. (however, your viewpoint seems good). Best regards