I have it and many of the techniques in it that were great 10-15 years ago are totally unnecessary today and even detrimental with modern CPUs.
It's still a good read and even though some techniques are obsolete, knowing them can help solving other similar problems simply because they can make you think about problems differently.
Um... Always? There used to be a time, not that long ago, when integer math was far superior to floating point math (see: Hackers Delight). Not so anymore.
via https://stackoverflow.com/questions/2550281/floating-point-vs-integer-calculations-on-modern-hardware
The video is a bit long so I haven't watched it yet, but it's LEA: Load Effective Address, "LEAL" is AT&T syntax for LEA (Intel syntax).
Here's a good comment on the topic by Peter Cordes: Using LEA on values that aren't addresses / pointers?
Before you start replacing all your shifts with LEA you should be aware that it isn't always faster. As with almost everything in modern CPUs it depends on what the CPU is otherwise busy with.
https://stackoverflow.com/questions/70316686/assembly-why-is-lea-eax-eax-eaxconst-shl-eax-eax-const-combined-fast