As a guitarist, I have often heard that it was not good to train your hand with certain aggressive strength training tools for you hand. Are the more aggressive tools for strengthening your hand (Finger Pullups, Grip Master, and the like in the image below). Many other guitarists swear by these tools as a way to improve their skill.

My concern is that these tools can increase the risk of Carpal tunnel syndrome for an already risky activity (guitar playing) in a world of risky activities (typing, keyboard use, computer mice, cell phones, etc.)

My question was inspired by the question here:http://music.stackexchange.com/q/2298/15535

The actual question is: Does the use of such hand strength training tools such as these increase the risk of carpal tunnel syndrome, and by how much?