Long time ago I think the standard method of attachment...of the leader to the line was a nail knot. Then at some point someone started using a loop made into the line and leaders with loops for quick attachment..??

First time I hired a guide out west, he immediately cut the line off and tossed the loop and we went with a straight , knotted attachment because he said that loops would cause the leader to "hinge" and I wouldnt be able to cast "straight"..? Soooo...thats how Ive done my attachments ever since....BUT

Lately ( because Ive been looking at a new 5 wgt line) I see the loops made into the end?? I have no problem clipping off that last 1 1/2 inch of line if the loop is useless or a hinderance...but is it?

What do YOU use? A nail knot or a loop??