Ability to add to selection set without deselecting already selected items

[Markus Barrera-Kolb]

Using select you can add additional items to your selection set. However, if your selection marquee includes something that's already selected it will be de-selected. While at times this may be the desired effect, I wish there was also an option for exclusively adding to the selection set.

Sketchup provides this option by using the key -- obviously this won't work in VW, since is already used in lieu of left-to-right crossing selection, so another modifier key would have to be used...