typos

etc/header.md

@@ -12,12 +12,19 @@ a while, you realize:
 - Everyone  could have more fun if we avoided the same 
   dozen or so traps.
 
-So I decided to write down that theory and those tricks and    traps.
+So I decided to write down that theory and those tricks and    traps (see below).
 I took some XAI code (explainable AI) I'd written for semi-supervised
 multiple-objective optimization. Then I wrote notes on any
 part of the code where  I had spent time helping helping people
 with  those tricks, theory and traps.
 
+
+Also, this is  "simplicity-first approach.
+The SE and AI literature is full of bold experiments that try a range of new ideas.
+But some new ideas are better than others. With time, a little patience,
+and lots of implementation experience, we can find
+the least number of best ideas, that are simplest to implement. These are shown below.
+
 Those notes  divided into five groups of things about AI and SE
 that you might want to learn: