The following opinion does not reflect the opinions of the Framemakers or any other person in the shop. These are strictly Opinion by Cyrway.
I personally hate the whole idea of "giclees." (French for "spitting" or "sputtering".) These "limited editions" are bogus. With lithography, one is sure the plates are destroyed. With giclees, hey, look, the file's right here on this disk! They're usually printed off the same machines that print out large photos. Yes, they're beautiful, but they're from an inkjet printer very similar to the one you have next to your home computer, just on a bigger scale. Anyone with an Epson R1800 and Photoshop can print out beautiful "giclees." Do I market my reproductions as such? Heavens, no. I could, but I won't. But I'll get off my soapbox on this one for now, because it will lead into my opinion on Kinkade.
The "canvas" used is usually canvas paper -- it really isn't meant to be stretched, especially on the larger sizes. By restretching, one risks separating the inks -- seen it happen, it isn't pretty. The smaller ones are usually fine, but when one gets above 14x18, the paper part sags and -- well, we all know what happens.
We here at the shop drymount it, usually to either acid-free foam or Gatorboard, using Fusion 4000 film. If the customer insists to have it stretched, we will use rag mat as a backing cut exactly the size of the bars, but very rarely do they go that route, unless it's signed and numbered, but again my opinion has been stated above. Many times it comes to us already trimmed to the image, which pretty much makes stretching impossible anyway.
We had wetmounted a Dr. Seuss seriograph printed on canvas paper to 8-ply rag and restretched it around the bars -- these instructions were from the seller of the piece and the conservator on duty.
Ultimately, the problem is not because of the "giclee" itself but the canvas paper it's printed on. But I think someone had already said that.