The "1"s in the memo were really "l"s. Whoever made this attempt wasn't doing a very good job.
What happened to the argument that typewriters don't have closed "4"s?
Those are definitely "1's." Look at the top of the character. You will see that there is only hash to the left of the top of the character, completing the "1." You can see the "I" shape in the second part of the example in the word "Interceptor."
Nice try though.
He's takling about lower case ell's, not upper case aye's, altho I'm not certain in which contxt, the original or the attempt to duplicate it. Given that some inexpensive typewriters had no "1" key to save the expense of that key, it would bereasonable to expect that someone who learned to type on such a machine would use lowercase "l"'s even if they had a "1" key on their machine.
