If I select multiple tasks, there are some things I can do that will affect all of them: set their color, for example. But there are some things that automatically reduce the selection to one task. I'd like to be able to do the following to a set of tasks:
-- Drag them right or left to change the start date of every task by a certain amount.
-- Enter +1w or -2d, etc., in the actual start date field in the inspector, to change the start date of every task by that amount.
-- Enter +1d or -2w, etc. in the effort or duration field in the inspector to adjust the amount for each task by that much.
And similarly for Cost, Completed %, etc.
-- Drag them right or left to change the start date of every task by a certain amount.
-- Enter +1w or -2d, etc., in the actual start date field in the inspector, to change the start date of every task by that amount.
-- Enter +1d or -2w, etc. in the effort or duration field in the inspector to adjust the amount for each task by that much.
And similarly for Cost, Completed %, etc.