The MSLS: Reloaded

"And now here I stand, because of you Mr. Stalder, because of you.  I'm no longer an agent of this system, because of you.  I've changed.  I'm unplugged.  A new man, so to speak, like you, apparently free."

"Congratulations."

"Thank you."

So I was originally going to add one more post on this topic, but this morning it's become clear there's the opportunity to add two related posts, and add in more neat nods to pop culture I enjoy.

This one was prompted by last night's video on cracking the cryptic, which is very much presenting the MSLS interpretation of the discussion.  I'm not entirely sure whether Simon actually reads this blog, or gets the information via separate conversations he may (or may not!) be having with Sam, but in the videos he is vaguely referencing conversations between myself and Sam.  My discussions with Sam have only happened here on this blog, so one way or the other they have to be the source.  I haven't heard back from Simon since pointing him in the direction of Trevor Tao's wonderful video, which I'm sad to say has not (to date) even had a vague reference on cracking the cryptic, so I can't say for sure whether it's a conscious decision to present this theory from one angle, or whether he is simply unaware of the extent to which all this discussion is influenced by many different contributions, Trevor’s certainly not withstanding.

Anyhow, I hope at least that my dearest readers will agree that all this stuff is far too interesting to not explore in plenty of detail and from multiple different angles. 

On to business.  Sam has come up with a wonderful puzzle which I'm pretty sure has been designed to completely bamboozle scanraid.  And it does.  For reference:

• The video is here: https://www.youtube.com/watch?v=uvTV_Wivxmo
• You can play the puzzle here: https://app.crackingthecryptic.com/webapp/dqTM27jm3P

However, I’d like to present it to you again with a bit of colouring in:

As I'm sure all my dearest readers are aware, this looks very much like one of Fred Stalder's examples as discussed in a previous post.  To recap:

• Here's my post: https://tcollyer.blogspot.com/2020/09/puzzle-350-sudoku.html
• Here's Fred's original post: http://forum.logic-masters.de/showthread.php?tid=1811&pid=32019#pid32019

The punchline to all of this is that instead of doing all the elegant MSLS stuff that Simon does in the video, you can instead make the following (simpler!) observations:

1. Thanks to Fred, we know that the digits placed in the blue cells plus a copy of (1-9) are precisely the same digits that need to be placed in the red cells.
2. There are 15 red cells with odd digit givens, and 10 red cells with no givens
3. There are 6 blue cells with even digit givens, and 4 further even digits in the copy of (1-9)
4. Therefore the 10 empty red cells must contain 10 even digits.

As Sam has pointed out on a youtube comment discussion, Fred gives you even more than that, but the observations above are all you need to serenely solve a diabolical-rated sudoku.

That's all for now folks - I still have one further follow up on this subject, again linking together some of the subject matter I've been discussing recently.