string()做我希望strconv.Itoa()会做的事情

I have a short program that converts a few binary numbers into their ASCII equivalents. I tried translating this into today and found that strconv.Itoa() doesn't work as I expected.

// translate Computer History Museum t-shirt
// http://i.ebayimg.com/images/g/qksAAOSwaB5XjsI1/s-l300.jpg

package main

import (
        "fmt"
        "strconv"
)

func main() {
        var binaryStrings [3]string
        binaryStrings = [3]string{"01000011","01001000","01001101"}

        for _,bin := range binaryStrings {
                if decimal, err := strconv.ParseInt(bin, 2, 64); err != nil {
                        fmt.Println(err)
                } else {
                        letter := strconv.Itoa(int(decimal))
                        fmt.Println(bin, decimal, letter, string(decimal))
                }
        }
}

which outputs

$ go run chm-tshirt.go 
01000011 67 67 C
01001000 72 72 H
01001101 77 77 M

So it seems like string() is doing what I thought strconv.Itoa() would do. I was expecting the third column to show what I get in the fourth column. Is this a bug or what am I missing?

strconv.Itoa formats an integer as a decimal string. Example: strconv.Itoa(65) and strconv.Itoa('A') return the string "65".

string(intValue) yields a string containing the UTF-8 representation of the integer. Example: string('A') and string(65) evaluate to the string "A".