Perhaps the best thing about the Yusupov books is that they train you in more ways than just the specific topics of the chapters. Every chapter requires calculation, and thus develops that skill. Also, the lessons force you to think about certain features of positions -- particularly if you follow his directions and use a real board and pieces, and play through the analysis -- which trains you to look for those features as well as teaching you what to do with them.
Yusupov and the Older Lower Rated Player

If you are going to play in a tournament, you have to play to prepare! The Yusupov books are good for background strength, but you need to get match fit.
Agreed. These 3 game affairs, which I play at two different clubs, are my preparation for real tournaments.

Today I finished up Chapter 2 of Boost Your Chess, The fundamentals. This chapter was on weak pawns. I scored 11 of 17 points. Nine points was good enough to pass. Twelve would have been a good. I had a chance going into the last problem worth 2 points. But I only got one, so pass it is.
Since this chapter was one of the strategy chapters, I thought I would struggle to even pass it. Fortunately that wasn't the case. I think part of the reason for that is I have been slowly going through Sam Shankland's book, "Small Steps to Giant Improvement" on pawns. I think that was a significant help to me in this chapter, especially since I haven't read the Kmoch or Soltis books. Shankland is really focused on the practical aspects of pawn play.
It's been two weeks since I finished beyond the basics 1. I havent started with the 5th book yet because I got interested in some other books. So far, I've read The Power of Pawns by Hickl and Simple Chess by Michael Stean. I am currently reading Soltis' Pawn Structure Chess, as well as Chess Structures, by Mauricio Flores Rios. The last two book are very informative and straight to the point books. I would like to go through Kmoch' Pawn Power in Chess, but that book is borderline incomprehensible, but I might give it a try nonetheless. I will also continue with Yusupov, but at a lot slower pace, because of all those other books I mentioned.

I was kind of surprised that GM Simon Williams didn't opt for this and instead played 1.Na5 here. I had to analyze it myself because Qe2 has to be right. Both are forced mate so it doesn't matter that much but it is still interesting to me.

No wonder it looked:
a) familiar and
b) wasn't in my big database.
Doh!
You're right. Qe2 is the more efficient way for Simon to win. In this defense, it was a simul and he wasn't (couldn't) taking much time per board.

33...Na5 is quite a difficult mating sequence with the best defense. It would make quite a good puzzle actually...
It begs the question if GM Simon Williams had seen that to the end. I would be impressed but not surprised. Qe2 is just much easier.

I suspect that he played Na5 because it was clearly strong, even if you could not be 100% sure it would lead directly to mate.
On the other hand, Qe2 is less obviously strong, and at first glance looks a little risky, like there might be some way of trapping the Queen.

My blitz skills are much less than overwhelming, but I did have a really nice poison pawn position tonight in a game. Black to play. If they play Qxb2 (and they did), it is curtains for them.
It's been two weeks since I finished beyond the basics 1. I havent started with the 5th book yet because I got interested in some other books. ...
I thought that Beyond the Basics 1 was the 2nd book, to be followed by Evoltion 1 and Review and Exam 1.
"... This book complements the three volumes in the Fundamentals series (Build Up Your Chess 1, Boost Your Chess 1 & Chess Evolution 1) with exercises …"
https://www.qualitychess.co.uk/ebooks/Revision&Exam1-excerpt.pdf
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I suspect that he played Na5 because it was clearly strong, even if you could not be 100% sure it would lead directly to mate.
On the other hand, Qe2 is less obviously strong, and at first glance looks a little risky, like there might be some way of trapping the Queen.
I was kind of playing "guess the move" and always delve deeper when I am completely confused on why a GM made a move other than one that is rather obvious to me, especially when their move looks suspiciously weaker (not usually the case at all), it is usually a good learning experience. Qe2 is quite obvious to me, hence the reason for my post. Trapping the queen isn't a concern at all because they would have to do it in 1 move (not going to happen) due to the threat of Nd3#. The possibility of Nd3 is what made me want to move the queen in the first place. From there it is just following the forced moves which seems easy enough. I'm sure he was playing fast and wasn't really that concerned but it is rather peculiar to me.

My blitz skills are much less than overwhelming, but I did have a really nice poison pawn position tonight in a game. Black to play. If they play Qxb2 (and they did), it is curtains for them.
Yeah, I guess they didn't understand opening the b-file is a bad idea. They just saw the 2 pawns they can snatch probably. I see 1..Qxb2 2.Rb1 Qxb1 3.Rxb1 and then probably 3..Kd7 because 3..b6 leads to 4.Qa8+ Kd7 wait, I'm trying to visualize but it is getting tricky here... I thought it was 5.Rd1+ but I'm pretty sure that 5.Qb7 comes first so that you can take the c7 pawn if the king moves. Maybe 3..Kd7 is worse but I don't think so. It will be interesting to see what the computer says.
Edit: 3..c6 is another option that I didn't visualize. 3 options and I only saw 2. And 5.Qxa7 is slightly better than 5.Qb7. I had fantasies of winning a rook... 3..b6 is way better than 3..Kd7 I could see what I thought was wrong with 3..b6 so I would of preferred the way more complicated 3..Kd7 but that isn't a good approach for accuracy but maybe practicality.
"... When we acquired the books, we originally only planned to publish one from each series. We all make mistakes. For this reason, the order which the books are intended to be read is not entirely obvious. The order is:
Build up Your Chess 1, Boost Your Chess 1, Chess Evolution 1 …" (2017)
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"... Fundamentals first, then Beyond the Basics and finally Mastery. Follow the colours! …"
http://www.qualitychess.co.uk/ebooks/QandAwithArturYusupovQualityChessAugust2013.pdf
If you are going to play in a tournament, you have to play to prepare! The Yusupov books are good for background strength, but you need to get match fit.