1. Well, you could just be browsing tables, sure -- but the diagram would be silently whipping around to bring into view the table that you're looking at -- no harm there, eh? Also - what could is the diagram sitting on a table that has nothing to do with the area that you're looking at?
Sure, Ctl+T is OK, but it's awkward to get there. It involves using the arms and hands, which are otherwise dormant, In fact, I'm so lazy, I never use the Ctl-T -- I just right click and Go To / In Diagram
2. Wow! Thanks for pointing this out. Of course, I have to move an arm again, but hey!