A method to make the task livable:
Select material, then use the arrows in the extended keyboard row to increase/decrease the amount of the selection. Experiment.
ETA: In order to use the method, the initial selection must be made using the selection tool located in the extended keyboard row. Thereafter, as long as you remain in that document, the arrow method will work if you use the formatting pallete to select. (Scrivener 1.1.1 (964))