Like in Logic, can you increase the range of selection in the time ruler without having to re select? Sometimes you want to add an increment of selection to what you already have selected (highlighted). 

So you want to reselect something without having to reselect?
 
How does that work

Ctrl + click

I think the OP means if he's selected a range, but realised he needs to increase then end.
 
The easiest way to do this is to move the Now time indicator to the new end point, then click on the Selection area:

I have written a Studioware panel that includes CAL scripts that has sliders that does that (as well as other functions).  It has two sliders that, when moves , adjusts the selection on the ruler.

The purpose of the actual Studioware panel is to enter common GS/XG discreet controller values and pitch bend values - but I added the selection start and end point position sliders.

Thank you. 99% here like to give an answer and be helpful and unfortunately there is a very few that would rather be sarcastic and watch themselves type. I was clear and it was answered. Thanks
 
ctrl + clk  perfect!

If you use "Shift" instead of "Ctrl", you don't need to click in Time Ruler, just click in the Track View.