I need to file this under, “I can’t believe I didn’t know about this one!”
So, here’s the problem: When you go edit a corridor model graphically from the contextual ribbon tab (such as Edit Targets), it’s very difficult to determine which region your cursor is in because the corridor is highlighted and a big blue mess.
How Annoying is This?
What to do? Well, simply change the system variable SELECTIONEFFECT to 0. That’s it!
Much Better!
Yes, this have been around for over a year. Yes, I’ve been complaining about it for over a year. Yes, I feel like a jerk for criticizing Autodesk for making this change and hurting my workflow when they allowed me to change it back.
I found this out thanks to Lynn Allen’s new “2016 Tips and Tricks” booklet. What else is new that you didn’t know about?
Civil 3D Plus 
June 4, 2015 at 8:54 am
AAAHhhhh…thank you Brian!!! This has been a real pain the toocus when teaching class!
June 4, 2015 at 11:47 am
Are you kidding me!!! I too have been complaining about that as well. I too feel very stupid right now. Thanks for posting, Brian!
June 4, 2015 at 11:48 am
I still blame Autodesk, they should be setting the variable for you and then to the same value as it was before the command is run. Around three lines of code are missing, yes that is the low effort required to fix this.
You could also do the change yourself by modifying the cui.