If I was fishing a 12 foot rod with a 9 foot leader, one might come in handy on occasion…
However, I like them because it adds a finishing touch to a rod like a winding check or tipping on wraps, other superfluous adornments that serve no purpose other than to look nice. As a result, save for a few custom rods where I deferred to the style of builder, most of my rods have them.
Regardless, I almost never use them preferring to loop the line around the back of the reel foot and attach my fly to a guide in the upper 1/4 of the rod. That accomplishes a couple of things; first, more line is out past the tiptop so any first casts done after securing the fly, line & leader are easy to begin.
In addition, when I want to resume fishing, all I have to do is unwrap the line from around the reel and let it drop, hold my rod horizontal to the water and lightly tap the rod blank in front of the grip with the palm of my hand once or twice. That “bump” and the resulting "jiggle" of the upper rod blank dislodges the fly so it drops from the upper guide and I’m ready to begin false casting.
Finally, when you have the line, leader & fly secured in this manner, you can wrap the belly of line around the rod a few times and "hook" it over a guide or two. That helps to keep from snagging loose line and leader on brush as you walk through the woods.
None of these tricks work if you just hook your fly in a hook keeper.