Heisig says in the introduction to RTK I that he learned 1900 characters "before the month was out". If like him you can do the whole set in a month and then have no further need of formal review or study beyond using them as they turn up, then I can see it not being a terrible idea. But as far as I can tell, almost nobody has a mind that works like Heisig's does: people seem to need longer and to rely more on review via an SRS like Anki.
Personally I found my problem with RTK was that I successfully memorised "English keyword to write the character" for 2000 kanji, but this was not at all linked to my actual use of the language, so I still had the problem I started with of "I want to write the word べんきょう but can't bring to mind the kanji for it", because I had no association between Japanese words and the English keywords for their component kanji...