I did not say that one should not to comply to a specification. There is a big difference between implementations complying to specification and implementations where the source code is basically just duplication of the spec (which obviously runs very slowly).
So my point is that even if the spec might say that "Do A, then B and then C", that's not what an implementation has to do EXACTLY as long as the outcome is exactly the same in both cases.
For example a property load is a hugely complex operation in the ECMAScript spec that would take thousands of instructions to implement naively. In practice e.g. V8 will in many cases get away literally with one machine instruction in best case. None of the specified property load steps are obviously happening but yet somehow V8 is spec compliant.
So my point is that even if the spec might say that "Do A, then B and then C", that's not what an implementation has to do EXACTLY as long as the outcome is exactly the same in both cases.
For example a property load is a hugely complex operation in the ECMAScript spec that would take thousands of instructions to implement naively. In practice e.g. V8 will in many cases get away literally with one machine instruction in best case. None of the specified property load steps are obviously happening but yet somehow V8 is spec compliant.