Howdy:
A couple issues. First, this is, for all intents and purposes, this is a community board. To the best of my knowledge Canon doesn’t use this for any input, and I see very little output from them on here. Usually they’ll weigh in on occasion with a quote from the users manual or a legal issue (e.g. pointing your camera at the sun may damage your sensor and void your warranty). But most the real discourse comes from people like you and me.
As to the ISO, ND. Unfortunately it isn’t as simple as simply turning down the sensitivity. The sensors have a native ISO, a level at which they optimally sense light. It is them amplified to hit the other ISOs. To lower the ISO below base you’d have to divide the signal, which would cause a significant reduction in dynamic range. Most people strive for higher ISOs, and there is a fix for shooting in really bright light (NDs), so the camera companies don’t really put time and money into low ISOs. I assure you if it was as simple as turning down the sensitivity then it’d already be done by someone like Magic Lantern or even companies like Sony and Pentax that actually innovate camera development.
Some basic info here:
http://photo.stackexchange.com/questions/9263/why-cant-the-iso-level-on-most-digital-cameras-be-set-...
And fantastic info here, though more technical:
http://www.cambridgeincolour.com/tutorials/dynamic-range.htm
