I have never seen the YAMAHA hookup in use...
Looks pretty simple in the video linked to here... Just plug the SIDEWINDER parallel cable to each generator unit and then plug your 30AMP Shore power cable in to the 30AMP plug provided with the sidewinder cable...
YAMAHA SAYS The Twin Tech Cables have a twist and lock receptacle, a heavier cable, and reduce Radio Frequency (RF) interference. The parallel power cables have a simple RV receptacle. So, if anything you are powering has wireless technology (including your radio) you will gain benefit with the Twin Tech Cables vs the Parallel Power Cables.
For me I wouldn't think there would be much difference. The Parallel Power Cable has the RV30AMP female receptacle where you can plug the 30A shore power cable directly into the adapter cord. The TWIN TECH cable having the twist lock receptacle will require you to obtain an adapter cord I guess.
Roy Ken