As a fly angler, in addition to the practicality of a given knots purpose and use is the practicality of implementing it in different conditions. There is often a lot of additional “tribal knowledge” on some of these knots, like the clinch knot is great but tying it with some hemostats speeds the process up and is easier when standing in a river. There is a great trick for tying a blood knot which makes it easy whereas doing it from the website would be nearly impossible outside in the weather.