Athletes will brag about their great swim, and how they may have improved 5 mins from one year to the next. But then you look at their T1 time and realize they were 4 mins slower in T1 this year. Net result is only 1 minute faster! All those hours working on the swim, all that improvement, simply wasted by a lack of urgency in T1.
If you know you will not have a sense of urgency in T1, then why are you working so hard on your swim? If you want to be economical and not waste energy, then just go easier in the swim.
Why not take a few of those swim sessions and spend it running, biking, napping, getting massage, or doing something else to improve. Why waste all your hard work? Why not figure a way to be quicker and more streamlined in your T1?
If you're worried about being too tired from the swim and feel you need to rest, why not just coast on the bike? Great way to rest, and still progress forward in the race.