So coming to this late, but since I have a slightly unique perspective, I’ll share.
I did RTK years ago (like ~10). I liked it at the time, got ~1500 kanji to mature in Anki. That, together with kana and grammar from Tae Kim got me to a state where I could “read” (understand, or at least decode) quite a bit of Japanese text. But I certainly couldn’t speak it, or understand spoken Japanese.
Readings/comprehension never came, though. Some basics were easy, but I never developed that “intuition” for it, despite frequent input.
WK, in the 3-4 months I’ve been here, has built me more of that intuition than several years of trying post-RTK. Why? Because by learning the readings in the context of vocabulary words here, I’ve found a lot of other vocabulary, either not in WK or at a higher level than I’ve achieved so far, that I already know how to read and can often infer meaning of due to knowing the kanji meaning and reading together from WK.
Even better, I’ve found a lot of these encountered words, I read in Japanese first. And more and more often, that’s all I have to do. I have the concept of what it means without translating to English terms. This is very new, very rare, but it’s pretty profound to me. I am understanding words directly in Japanese.
RTK was great, don’t get me wrong. I can progress in WK much faster because of my RTK pre-knowledge. I basically ignore the WK mnemonics for meaning, since most of the kanji I know already or pick up/relearn quickly. But it will never, can never, get you to the point where you will be understanding Japanese in Japanese.
If I was doing it over, I would have done WK without the separate step. It would have taken longer than WK after RTK, for sure, but it probably wouldn’t take as long as RTK followed by WK as I’m doing. And I wouldn’t have delayed getting to this point where Japanese starts to make sense as long as I have.
TL;DR Despite doing RTK, I didn’t develop reading intuition until I learned a lot of readings. I learned those by doing WK. And that jump started my learning to an immense degree.