That site offers a number of products that can cause damage to other parts of the camera. Specifically compressed air! If there is any water in the compressed air it will condense upon being released and propel ice into the camera body with some force. If any solid matter is in the propellant that to will be shot into the camera body. There are several small fragile parts within the mirror box that could be damaged or bent by forceful blast of air.
Read the disclaimers and you soon realize you take full responsibility for any damage to your camera!