Hull widths;
Mr Yost's Nomad, DragonFly and FlashFire, and the Peregrine that was taken from Nomad are all 28.5" wide. Bell's Merlin II was 29" and Swift's Kee 15 is 29.5. I find these facts difficult to resolve with the opinions above. The increasing width of Mr Yost's solo trippers reflects the success of McDonald's "Super Size" campaign. Solo paddlers are getting heavier. Further, there is some difference in waterline width's; shouldered tumblehome results in tighter waterline widths than bubble sides of the same overall/max width.
Tracking is mostly a function of block coefficient, and calculating/measuring minor differences between these hulls would take time. It i useful to remember the second factor in tracking is paddling technique. Carrying the blade aft of the body always yields a fine view of all four corners of the lake.
If one is wide enough in the shoulder to stack hands across the rail, more recent subtle changes in design probably allow his more recent hulls to track as well as the older ones. If one is long enough in the leg to plant knees in the chines, the more recent, wider hulls will spin more easily because heeling the wider hull lifts the stems higher. For moderate heels the newer stepped bow rocker, intended to increase speed, will clear more readily, enhancing skidded turns.
Discussion of comparative handling, speed and dimensions of Yost's Curtis NorthStar/Hemlock Eagle and Swift Kee 16 seem to have little basis in fact. Certainly the Kee 16 has differential rocker, despite claims to the obverse. Rocker can be evaluated with a string and two friends; two folks stretch the string, the third takes a cell phone image from the side. Eagle has 2" symmetrical rocker, Kee 2.5 in the bow, 1.5 in the stern. I personally prefer significant and symmetrical rocker, but most stern paddlers have the counter productive tendency to carry the blade aft of their body. This results in yaw towards the bow paddler's side which the stern's J then corrects. Modern design thought features less stern rocker than bow to counteract that induced yaw.
Stick skills of unknown tandem teams, and their analysis of handling are best viewed with a health dose of skepticism. We can't determine if compared boats are properly trimmed, which has a huge effect on handling and speed. We can't evaluate skin condition, a huge factor in slower speeds. Multiple time trials over measured distance would provide real data, but " I think it's faster" isn't very helpful. A slower hull could make more noise and seem faster. Even swaping boats won't counter human tendencies. If we want one boat to be faster it generally happens that way.
Stating that DY's 1985 16'X35" river tandem is faster than his 2012 16'X35" touring tandem kinda begs credibility. If the waterlines are identical, we'd expect the "two wave wash", or theoretical hull speeds, to be the same, following the formula; Sq. rt. of wl Length in feet X 1.55 = mph. The suggestion that Mr Yost has not learned anything about hull design in twenty seven years is kinda funny in an absurd sort of way.
Confirmation bias occurs naturally, we all want the hull we love to be faster, tighter turning, whatever, than other canoes. We've all owned the best dog in the world. As "campfire talk" it's harmless. Typed out on the internet, it becomes an example of Dunning-Kruger Effect and proceeds to mis-inform a generally innocent public for years.