Drive-by sketching?

I've probably driven by Covenant Hospital 1000 times in my life, but this morning I had a few minutes to kill between meetings so I decided park into an adjacent parking lot and sketch it!  My goal was to capture the essence of an architecturally complicated hospital complex and to do it quickly.  I needed to decide what the iconic view of the hospital was, compose and simplify the sketch and then execute the sketch.  Beginning to end...55 minutes.  I'm not sure how successfully I accomplished my goal, but I sure had fun!  I'm trying to get better at seizing opportunities to hone my skills when they come along...