I tried to use a filter to limit scope to all Canon cameras via the Category selector, and then to use timeline view for 2003. This, however, doesn't let the files be grouped by model, even if I specify to show hierarchy for all levels. Can the Date section in the filter panel allow quick selection of all images in the year 2003. If so, how?
To see files grouped by model, use a data-driven category.
If you often need to see files grouped by year and camera model, setup a data-driven category with year on the first level, and camera model on the second.
To select ranges in the date filter, click the start and <Shfit>-click the end of the range. You can scroll the date calendar as needed to bring other months into view for further selection. If you suggest enhancements in the date filter, please do so via the feature request board.
The timeline is the best view to select files based on date. If you need the files for specific processing, just select a year and put all the files in a temporary category (use the script in the context menu: Create category from selection), or add a pin, dot or flag to mark them. This allows you to easily filter on these files in any of the Views. That's what pins, dots bookmarks, flats, label and ratings are designed for.