I dare to disagree that PE8 is the minimum choice for doggies. Of course, there are situations, when it is good to use such a thick line, but in general situations one has to be aware of its disadvantages:
- In depth more than 80-90m it would be very hard work. You have to use heavier jigs and can not use a fast jerk technics ("from the hand") so liked by doggies sometimes during any long period of time because of your fatigue.
- With such a thick line you will be limited in your tactics. You will have to make less retreives during one drift, because the line angle. And you won't be able to fish next-to-bottom layer for long.
The main idea is that the line selection should be appropriate to the used rod, not the fish. It is the rod that makes a pressure to the fish, and line is just a link. Many anglers have their line broken just because they use rods stiffer than it is appropriate for given line. Or vice a versa, some use thicker line than reasonable for given rod, which makes it difficult to work the jig, though give you no advantage in fighting the fish. There are rods which provide you less fighting time with PE5 than other rods with PE8. So, I think it is not correct to say that "dogtooth must be fished with PE8 or PE6" or any. The line should correlate to the rod and the fishing conditions.
It was mentioned that the rod meant to be used is Smith Nirai. I see no reason to use PE8 with Smith Nirai which is a relatively soft rod with relatively low lifting power. I used such set up and I think it won't give you considerable gain in stopping and lifting the fish in comparison with the case it is equipped with, for example, PE6. If you use Nirai, and especially in the big depth, I would recommend you to use PE5 or PE6 set up and make a shock leader longer. Long shock leader will be a good compensation to the high drag and make it possible to use high drag settings with thinner PE like PE6. Fortunately, this is not casting where we can not use 7-10m shock leaders.
As for the impossibility of successfull release, I think most of doggies bigger than 50kg lifted from 100m depth are hard to be safely released, unfortunately. This is one of the the reasons I tend to like GT casting more recently.