In 2003, there was some buzz about switching to 2-D chromatography to improve the separation of some of the "piperylene" (1,3-pentadiene) streams at the place I work. However, there were some massive layoffs and cost cuts that put a hold on GCxGC testing and it has never been restarted. Here are the references to few review articles that I gathered at that time:
-Journal of Chromatographic Science, vol 29, 1991, Liu, Z.; Phillips , JB
-Journal of High Resolution Chromatography & Chromatorgraphy Communications, 1987, Vol 10, Giddings, JC.
Book "Multidimensional Chromatography", edited by Mondello, L, Lewis, AC, Bartle, KD, 2002. Ch 4.
Never got any experience in the subject, although I've since heard that an ASTM test using 2D GC has been approved.