2 into1 vs. 2-1-2

[Leadfoot]

What is the advantage of a 2-1 system over a 2-1-2 system? The new Street Glide and Road Glide have a 2-1 system now? Harley is advertising this like it's a good thing.

[Blackdog 15]

2> 1 uses the pulse of one cylinder to help draw the next cylinder gases out thus exiting spent gases very efficiently...great for torque, & power...same system as a Thunderheader...(what I run)...

[Leadfoot]

Thanks!