I can only imagine what it must have been like back during the war when radio operators would sit for hours on end just receiving and recording Morse transmissions. They would have had to be good at copying and also transcribing what they hear. Fast code is something you will clearly get better at after hours of copying but writing the text, especially if it's encrypted and the characters do not form logical words. I guess the OPs would have no choice but to get better hour after hour. I do not know how fast code was transmitted back during then but no matter the speed the OPs would surely be capable of keeping up.
I would really like to start improving my copy speed to about 20 wpm or better. I know with practice this will come but I do not operate often enough to just "get better". Logically, plain language text is a lot easier to copy because your brain works to predict what word is being spelled and most common words come up more frequently. The problem is that point where you cannot write fast enough to keep up with the transmission. I can copy higher speed contest call signs after I hear them a time or two but I have difficulty in a standard QSO if anything "out of the ordinary" is causing me grief. When I say "out of the ordinary" I really mean "ordinary" because QRM and QRN are there more often than not. As well, an OP with strong swing or who runs his words all together with very little space between them is quite common and that messes me up every time. Operators who do not slow down to my speed cause me grief and don't even get me started on all the abbreviations. It seems there is always one to stump me. All these things which occur regularly are the things I need to work on to improve. Incidentally, here is a link to abbreviations and Q codes and more.
The real stumbling block, for me, is that transition from hearing the "letters" to hearing the "word". I'm not sure at what point that "a-ha" moment will come but I'm pretty sure it is the key (no pun intended) to copying the faster OPs. More on air time will help but practice with a code generator or listening to QOTD* podcasts at a higher speed is the thing that will put me over that line.
QOTD or Quote of the Day is a series of daily podcasts at various speeds of CW. They are real language sayings converted into CW and last for a few minutes each. You can subscribe to them with your Podcast player and they are delivered to you. I really need to get back to those. If you are interested in them you can search with your player or go here.
Cheers for now
es 72 de Scott ve3vvf