[svat]

Also, as I counted when this came up a few months ago[1], only a very tiny part of the TAOCP books is in MIX. For example, in Volume 4A, there are a grand total of 3 programs in MIX (and 2 of these in Answers to Exercises), over the 883 pages of the volume. Even in Volume 1 which has the most, there are only 36 small MIX programs over the 652 pages.

Knuth gives MIX programs only when it makes sense for a specific purpose (“…makes it possible to carry out meaningful studies of the effects of cache and RAM size and other hardware characteristics (memory speed, pipelining, multiple issue, lookaside buffers, the size of cache blocks, etc.) when comparing different schemes.”). He even gives C code sometimes, e.g. in Volume 2 when presenting a summary of the chapter on random numbers, there are five C snippets on pages 185–188.

Anyone who doesn't want to learn MIX can just ignore those few parts of TAOCP; there's enough value in those books without them. A good place to start may be the most recent fascicles[2].

[1]: https://news.ycombinator.com/item?id=14520230

[2]: http://www.cs.utsa.edu/~wagner/knuth/