I spent a year in Minneapolis last Thursday, and carried the whole time. I have a Bianchi IWB that isn't tuckable, so I just pull the dress shirt out in that small area.
I have practiced the draw, and it is fast. I don't need to use both hands. I just come up with my thumb under the shirt, wrap it around the grip, and by the time I have my whole hand on the the grip the shirt is completely free.
To me it was very easy to see I was carrying, but I only saw one confirmation that others could. It was insurance license continuing education, and in the ethics section a topic led to the instructor (from Texas) asked if Minnesota has the castle law. I was the only one to respond ... I carry on the right side, and for the meeting I was sitting on what was my right hand end of the table (on the center aisle) where the speakers could see me easily ... When I answered that Minnesota did, and she had to explain to most others what the castle law is, she looked back at me and winked. Now ... I didn't just fall of the turnip truck, so I know that this babe wasn't taken in by my athletic physic and charming good looks
One nice thing I learned about this style of carry is that when I needed to stop for gas after 10 PM, and some less than polite customers arrived, I just tucked my shirt in. In five seconds I can go from concealed to open or back again.
Have I ever explained to you how much I hate the city? I spent eight years in the LA basin of southern Cal and hated every minute of it ... To this day I'm surprised I didn't run away from home. Maybe that is why my mom sent me "back home" every summer to work and spend time with relatives.