I understand your motivation for this. Our 30A coils into a small compartment. Making 8" coils out of this heavy cable isn't much fun, but I know it's easier than poking it into a hole your hand won't fit into is even worse. That said:
Never seen a shore tie cable fail in the middle. At least one that hasn't been run over by a bulldozer, hit by a mower, etc.
No, all the problems happen at connections. Receptacles, Plugs with scorched contacts, screws holding wire in connectors, etc. So I'm actually glad to have only one end to be careful about. If you mount your own twist-lock like that Marinco, you'll probably do OK with it. Still, I had my own home made extension cord. My own RV shore tie plugged into it. Loud knocking on the coach. Outlet box was on fire! I did a temporary splice, then made it permanent at home. Connections crimped then soldered, padded out to cable diameter with tape then shrink wrapped. More cable to coil into that little compartment, but a JOY to have one less plug-in. Just sayin' and YMMV.
There's a BUT with built-in: If the splice between the flexible shore tie cable and the hard wire leading to the breaker box isn't very well done, it can burn out and go open. Happens regularly on 30A coaches when they run two electric space heaters.
If God's Your Co-Pilot Move Over, jd
2003 Jayco Escapade 31A on 2002 Ford E450 V10 4R100 218" WB