SSL offloading for https traffic

do you mean combine? should be as simple as:

when CLIENT_ACCEPTED {
    if { [TCP::local_port clientside] != 443} {
        SSL::disable clientside
        SSL::disable serverside
    }
}
when HTTP_REQUEST {
    set uagent [string tolower [HTTP::header User-Agent]]
    if { $uagent contains "msie6" or $uagent contains "msie7" or $uagent contains "msie8" or $uagent contains "mozilla/4.0"}{
        pool pool1
    } else {
        pool pool2
    }
}