I ran through the EAC configuration wizard, to see how it's choices would compare with my manual setting of Lame parsing with command line options --alt-preset standard -b32. When I looked at the compression settings after picking the r3mix recommended settings in the wizard, I saw that it uses these "Additional command line options:"

%l--alt-preset 128%l%h--alt-preset standard%h %s %d

and it has selected "User Defined Encoder", with the path to my lame.exe.

Can someone point me to an FAQ that explains what the %l...%l, %h...%h, %s, and %d do?