Is it necessary to draw my alpha blended polygons back-to-front? Or is it possible to simply draw all the normal polygons, turn off the z-buffer, and draw them in any given order? Will there be artifacts in the latter scenario that would not be present if I sorted them?

You have to have the Z-Buffer ON to be able to draw them in any order you want, the Z-Buffer then does the sorting for you. If you don''t have the Z-Buffer on then you do have to draw them back-to-front.

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- outRider -

You must draw alpha blend polygons back to front. If you turn off z and then draw them any order you will have them everywhere! The only thing you could do is use the stencil buffer and draw them front to back by drawing the polygin into the stensil buffer, turn off z draw with stensil op, turn off stencil op, turn z buffer on, ..... much easier just to draw back to fron for alpha blend polys.