If an annotation extends below the idea, the column width could switch to full screen immediately, rather than waiting for the start of the next annotation. At the moment, a long annotation that occurs close to the bottom of the idea will continue in narrow column format for its entire length, leaving lots of unsightly white space.
If you change that to 'next paragraph' instead of 'immediately', I'll at least tolerate it, but I think it's better as it is. Having things change width in mid-read is uncomfortable.
Almost anything is possible, but as jutta's script uses HTML tables for organization wouldn't changing column width in mid-annotation involve rebuilding the whole shebang so that annotations can be split into multiple rows and cells on the fly? Remember too that different screen resolutions will cause the break to occur in different spots for different users. Click the "view source" option on your browser and take a look at the HTML for this page, for instance.