I'm a fan of single strand....it's thin, hardly visible and prevents Mega GT's from pinching mono apart with their teeth or jaw pressure.
Haven't used 040 Gal like Steve though I do use 120-150lb single strand...even hawk-eyed yellowfin eat the stick baits n poppers with this attached!!!
I feel more confident when it's a big GT location to have 45cm of single strand wire as a GT mouth guard!!
There was a pic of Tim Baker I saw of the first 60+kg NOMAD got...he's got his arm up to his shoulder inside the GT's gob retrieving the swallowed lure...thankfully teflon bread boards make great GT mouth spreaders!!!
If a guy who is 6'3 needs to put his arm that far down, how bad do you want to stop a GT from biting you off on heavy drag?
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For me, it's 45cm of wire backed up with a 150lb twisted wind on!!!!!!!!!!!!!!!!!!!!!
Aaron.