"Important progress towards high bit-depth and non-destructive editing in GIMP has been made. Most color operations in GIMP are now ported to the powerful graph based image processing framework GEGL, meaning that the internal processing is being done in 32bit floating point linear light RGBA. By default the legacy 8bit code paths are still used, but a curious user can turn on the use of GEGL for the color operations with Colors / Use GEGL." http://www.gimp.org/release-notes/gimp-2.6.html
Clearly this artist was not a curious user.