wasn't there a post about laddersafety.com or something??
Wait a minute, let me check ...................
here it is
http://www.laddersafety.org/
take a look at that
Now I'm confused about the ladder you are thinking about. You said
"m/t 17 werner adjustable ladder" Is that an A frame ladder like the Little Giant? I know they make a tall one. If that is the ladder, you should be fine. If you feel uncomfortable on it, then you have another issue, IMO.
Now, if it is a regular extension ladder and you are insistent on doing this after all the advice, put some rubber roofing under the feet and make sure your angle is just a wee bit steep. By rubber roofing I mean the stuff they put under the asphalt shingles to prevent leaks from roof dams. I used some a few years ago on a slate floor and then we had planks on the ladders. It was incredibly secure. But I tend to be a little fearless on ladders once I got my legs.
Also pad the feet against the walls. I actually have made a board with carpeting on it because sometimes I am FORCED to lean a ladder against wet wallpaper and need to spread out the weight.
But remember this PRIMARY rule, If you feel at all uncomfortable,. DO NOT PROCEED. A case of the nerves will cause an accident even if your set-up is safe.
Rolling staging would be by far the safest. I think a baker type can be as high as fifteen feet (with outriggers). If I was painting a lot of tall foyers, I would have invested in one many years ago.
Just remember the old clique,
Safety is no accident