I used a trip line with my Rocna maybe 10-20% of the time. I suppose it's like concealed carry-- if you're doing it for a 'just in case' moment, you need to always do it or the one time you need it will be one of the times you didn't bring it with you. (now on to trip lines...)

Since my anchoring depths ranged from 25' to 80' on average, I needed at least an 80' trip line. Btw, the type of anchor isn't the issue in whether or not to use a tripline, it's the likelihood of snagging and gear loss. Here in the PNW, there are many former logging sites that make the best, coziest anchorages and the bottom is littered with cables, chains and waterlogged trees. The risk is quite high. Rocna owners may tend to consider trip lines simply because the anchor is designed to easily utilize them (as are som other anchors...)

I usually had to coil up and secure extra line somehow between the float and anchor, it was usually an ugly job and untangling it after recovery was never something I enjoyed but simple enough to do. I also used floating yellow line so that I could see it but at low tides, sometimes my coil also floated at or near the surface and sometimes 10-20' from the float.

This next time I'd seriously consider non floating line and having several 30' lengths that I can tie together for the deeper anchorages. If I don't have a bundled up/ coiled, floating mess of line, then I don't think there's any real chance of a passing boat messing up the trip line. Another feature in the PNW is our windless nights where the boat can float all over the place and the trip line can snag my OWN props/rudders, etc