A similiar proceedure was used for raising the Kursk
Title says it all. In order to raise the Kursk they had to saw off the forward torpedo section with a chain saw similar to what they used on the Tricolor. With the Kursk they made only one cut and left the dangerous torpedo section on the ocean floor. Apparently with the Tricolor they made many cuts and brought up the wreck in sections. This is very impressive salvage technology. I suspect the expense involved is justifiable only if the wreck is a menace to navigation or an environmental hazard like the Kursk.
Gary