My guess is the same as knelson.
Where did you get the workout? Can you ask the person that wrote the workout? If it is from a book or on-line there may be a list of terminology somewhere.
My guess is "smooth" means easy swimming, concentrating on technique. "Touch and goes" mean swim these continuously with just an open turn at each wall, presumably as fast as you can.
When I use the term 'smooth' in my practices, my focus is having my swimmers get easy speed by keeping their strokes long and relaxed.
I'm not sure what touch and goes refer to but I'm in agreement with knelson's thoughts.
Paul W
Touch and go to me means the minimal amount of effort required to make the send off. For example, if the send off is 30 you would swim a 29 and immediately touch turn and go on the next rep.
Seems to be missing some information. Like time intervals or effort required. If this is all the information the coach gave, he/she is not very helpful in structuring the set, or too reliant on terminology without giving some definitions. Ask the coach for more instruction if there is any confusion and the way this set is presented, I see plenty.