Allow the arrow with annotated text to be drawn as a straight line, instead of one that has a 90-degree turn before the arrowhead. The attached file shows a screenshot with such an arrow (annotated "prior information"), which was creating by hacking the file annotate-equations.sty and adding a command called \annotateS. I do not offer the hack as a code contribution, because it is not done very well, and I suspect that the original author could very quickly create this command in a more elegant and versatile implementation. Note that the equations shown in the screenshot were typeset with the gather environment.
Allow the arrow with annotated text to be drawn as a straight line, instead of one that has a 90-degree turn before the arrowhead. The attached file shows a screenshot with such an arrow (annotated "prior information"), which was creating by hacking the file annotate-equations.sty and adding a command called \annotateS. I do not offer the hack as a code contribution, because it is not done very well, and I suspect that the original author could very quickly create this command in a more elegant and versatile implementation. Note that the equations shown in the screenshot were typeset with the gather environment.