Hi snowman,
What I was quoting is worst case. Obviously wire paths should be as short as is practical. Since voltage drop was an issue for me and since panel prices were much higher ($5.50 per watt), and since I had to deal with a #10 prewire I chose MPPT and a panel output voltage of 33.
PWM operates at the battery voltage.
Jack's site is to the point. Handy is not. That's all.
Every system is individual to the needs of the particular camper but there are some guide lines that cover most situations.
Use the kiss principle.