It is not. Cat is still spelled cat.
I passed my 20 wpm morse code license 30+ years ago, and when I hear code to this day, it sounds just as natural as someone spelling cat as "See Aye Tee".
Morse code is not a new language, but it is a new way of writing, which is almost the same as a new language in many ways.
You get used to it, though. Your brain does the translating. I don't even see the code. All I see is blonde, brunette, redhead. Hey uh, you want a drink?
- You can memorize the letters and decode up to around 20 WPM. But this is using the low-bandwidth, logical part of the brain which simply isn't capable of decoding much beyond 20 WPM.
- To go beyond 20WPM you have to hand-off the processing to the subconscious mind. This is the phase that's equivalent to learning a new language. It requires a tremendous amount of repetition to build the mental muscle memory to hear the letters as a single sound instead of a series of beeps. It literally took years of daily practice to get there.
- Once you've mastered the individual letters you eventually start hearing combinations of letters as unique sounds. And at some point, you start to hear entire words, not letters.
- If I attempt to perceive individual letters at higher speeds I almost always end up missing the rest of the word. At these speeds, the conscious, logical brain becomes a liability that must be to be surpressed to decode effectively. As a 30 year software developer, this has been VERY difficult to do.
- When I get into the flow, I don't "think" about the letters or "hear" a series of beeps. The words somehow just magically pop into my mind.
Morse code is very much like a language in that there are audible intonations that differentiate between See, Aye and Tee. Being able to copy that in your head is the same as listening to English and not needing to reach for the dictionary every other word.
- hear di-dah (sound), think dot-dash (printed symbols), in the table that's an A
- hear di-dah, think "A"
- hear dah, di-di-di-dit, dit, hear the word "the"
- add more and more words
Along with that progression, the mental buffer got bigger, as it has to in order for you to recognize whole words. If I was having a conversation near my speed limit, a good way to break me was to send a long unusual word
Some other things that surprised me and may be interesting for other people:
Learning Morse code is like learning a new language. The unit of understanding is not dots and dashes but rather every letter is a unit that one (in modern training) learns to recognize intuitively as such before doing anything else.
On top of that, telegraphy has these three letter Q-Codes where one would assume that these abbreviations are for line efficiency, but also it's because three letters is a nice length that still decodes intuitively as a "word". (Also Q was probably chosen because it so seldomly comes up in "normal" words, so it's like a little attention signal? But that is my speculation.)
One can see in conversation that these three-letter codes often only have to be transmitted once, whereas free text (e.g. proper names) are often sent with redundancy so it's easier to transcribe them as you have to fall back to decoding individual letters. (My ears still sometimes perk up suddenly when hearing Morse code from movies because suddenly I pick up something like CQ without even paying attention.)
People therefore use terms like "musicality" (at least in my language, not sure if that translates to English) to refer to the quality of one's transmission. There is a certain art to it.
One funny exception to the three letter codes that gets used in Germany. If somebody signs off for a lunch break, they'll key ESSEN (translates to "eating"/"food") which would be considered "too long" to decode intuitively but it has a nice drumroll to it so it still works :)