As a Master at Arms I was required to use a lanyard with my 1911s and M9s, makes sense on a ship really. The one issued at the time was the annoying boingy phone cord one. Everyone hated that thing, got an old style one pretty quick. It really becomes a non issue quite quickly, and does have a comfort factor involved, whether walking a ships deck or bouncing across the desert in a Duece and a half.
I could see wearing one addtional magazine lanyard were I mounted, attached to the one in the gun, for that first reload. After that, things are probably too far gone to care!
Interesting that the only lanyard magazines I do have, are for my Tokarevs! Must not lose the peoples magazines, perhaps?