Not to confuse things, but I used to use a DT10F line in the surf. There's an advantage to the long distance mending that a line like that can handle. I don't have one now but if I did, I'd use it.
Rip, I thought this might come up when I posted. My thought is that since he's just started, casting the larger flies will be his primary issue and he'll likely get the best use from a WF. I don't think his concerns will be that much on mending line at any great distance where he'll be fishing.
You're point is certainly a valid one, and something that might have some use once he gets some experience.
I've also cut back sections on WF lines to get more weight up front. However, if he starts with a line designated for throwing larger flies to begin with, he'll likely not have to get into that until later on.
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