Invisibility of the need coupled with no administrative decree or support from many academic institutions 8. Do not put in any graphics that do not have an alt tag. Make the alt tag more important. Make the alt tag meaningful. When in doubt about using frames and how they fit in with accessibility, do not use frames.
Tables are always less accessible.
This is something that should be addressed at the html code level for the future. In the mean time there are hints about tables. If a table is used to present data that would normally be in a table, make sure that the columns are labeled, that the table reads left to right, column to column, and always give a caption with the table, and usually a text interpretation of the table. If you don't understand them, then you should learn. Style sheets are huge time savers and they also make your site much more accessible.