I ignored the minimums and use the largest size I could fit thru the lifeline grommets of my boat. I think it was 1/4" but it may have been 5/16 or 3/8. It is an intersting issue since the chaff guards add a lot more chaff resistance than upsizing the line, but the extra line size adds a lot of safety margin. For my cruising boat I went with the largest size possible. For a race boat I would probably go with dyneema chaff guards on the minimum size line, for a cruiser the largest size that would fit.While we are on the subject of lifelines, what size of line are people using for the actual lifelines made out of dyneema, amsteel etc?