Great tip Alex - the hits just keep on coming don't they?
With regard to Karl's reply - GS has definitely cut a corner here (pardon the pun!). This dialog must be their standard for any fillet/chamfer. I first noticed this when I tried chamfering a corner of any polygonal element, (roof, slab, mesh, zone, fill). Even though the fillet icon is what we select in the pet palette, the fillet/chamfer dialog is what appears next.
It also seems to me that the intersect command will work with arcs and/or lines (but not polylines or splines), yet the fillet and chamfer commands will work only with lines. Furthermore, all of these commands are under the *Line* Extras menu, which contradicts the logic (and confuses new users who have been using) the 'Line' flyout tool in their unextended tool bar. These commands can also be used on walls - just don't try it in the 3D window. Maybe it's because we won't find any (2D) lines in there?. As mentioned, some of these commands can be used on polygonal shapes and all of them should be incorporated into polygonal editing more uniformly. Line Extras? Hmmmm....
GS needs to allow us to intersect, fillet and chamfer all lines, arcs, polylines and splines, walls with comparable geometry and all polygonal shapes. They should also either have separate fillet and chamfer dialog boxes, or preferably a radio button on their existing fillet/chamfer dialog box, which will save them adding a new icon in the pet palette. It just may mean they need to change it's appearance.
Lastly, I recommend to all the new users I train to assign Ctrl+I to Lines Extras>Intersect. It's set to Teamwork>Sign In by default, but even if you do use Teamwork, you are bound to intersect many more times a day, than you will be signing into a Teamwork Project.
Cheers,
Link.