I still do this sometimes, but since I use a very old version of PS, I stack the layers and then manually use the eraser with diffuse edges, first with two adjacent layers, then with one more, etc... Until all are done.
I had read long time ago an article with an ingenious solution hare: http://www.graficaobscura.com/depth/index.html but I could never get used to it, so I had to think of a workaround and "discovered" the technique described in the OP. For lack of a better term, I called it "pseudo-DOF".
:)
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Alberto Tirado
Alberto Tirado
From: John Palcewski <palcewski@xxxxxxxxx>Overcoming the Challenge of Depth of Field in Macro Photography