Moss I had noticed that too. I've also seen post of people using it for a descender.

The splash screens on their web page for these two products differ in their suggested usage. However, if you read through the enclosed product literature, you will see that Petzl does show one graphic example of the GriGri being used as a solo decender.

The GriGri documentation does specify “short” descents.

The GriGri, like all Petzl products, is bullet proof so it’s not a safety issue, just a usage thing. The GriGri is a sweet gadget but I am exempt anyway since I spend 95% of my time on full half inch arborist line.

Short trees - Fat ropes,
Jersey climbers unite!

Yep, Grigri is my numero uno SRT descender, use it with 10.5 mm static and 11mm Fly semi-static. It's fine for long descents. I believe that Petzl recommends it for short descents as a "cover their butt" legal strategy. If you let it rip from 100 ft. on a Grigri it will get very hot. But then again any descender will to varying degree depending on the _meta_l mass and heat dissipation qualities of the particular design. The usual tradeoff: the more _meta_l and weight on the descender, generally the better it will conduct and release heat. So it depends how much you're willing to carry to the climb site and on your harness while climbing. I never fly down fast on rappel out of a tree so it's not an issue for me no matter what the height.
-moss