Hmmm, I've been thinking about it too. I can see that the descriptive approach would be far more useful to a wider range of people for who access is not straightforward. It puts the 'decision' with the person themself, rather than making a potentially flawed judgement 'on their behalf'.
I often try to make my instructions on how to get to sites quite detailed esp if nobody else has already posted detailed instructions here. I guess I may have inadvertantly given clues on some occasions, but I have to say that I've never thought about disabled access to sites so far.
I'll be trying to remember to give it a go when I next write fieldnotes - which will be before long!!
love
Moth