No, x86 has a lot of other shit that ARM does not have, and it becomes extremely difficult to strip that down to a smaller number of pages. I would guess you could take that down to maybe 900 pages if you paint using the high gloss. Most of what that 3439 page manual is about are the memory systems, a brief overview of coprocessors, and all the hex instructions and the limitations of the operations (fun fact, Jcc can only take a value from cl.), but the biggest difference is that x86 has a variable length instruction set, while ARM is always a 32 bit (IIRC) instruction set. Also, every x86 instruction has a varying execution time for each instruction because some idiot thinks microcoding is more speed efficient than a hardware solution.
The x86 book does not cover out of order execution, either. That's what the 1200 page x86 general optimization manual is for, and then you will also need the processor family's optimization manual (400ish pages), and finally the multithreading development manual (oddly enough, just under 200 pages) if you want to take advantage of hyperthreading or just splitting tasks efficiently. Onboard hardware also gets it's own book even though it is integral to the system. I haven't read into it too much yet, but I think the manuals actually cover things like exactly how the Out of Order Execution is performed and stuff.
The x86 book does not cover out of order execution, either. That's what the 1200 page x86 general optimization manual is for, and then you will also need the processor family's optimization manual (400ish pages), and finally the multithreading development manual (oddly enough, just under 200 pages) if you want to take advantage of hyperthreading or just splitting tasks efficiently. Onboard hardware also gets it's own book even though it is integral to the system. I haven't read into it too much yet, but I think the manuals actually cover things like exactly how the Out of Order Execution is performed and stuff.