Earlier quoted context omitted.
Branches that are hard to predict should be “hand-optimized” through specially written code, compiler intrinsics/annotations, or profile guided feedback to tell the compiler to emit the conditional using unconditional branchless instructions like cmov. Expecting a CPU to detect this at runtime may be asking it to do too much.
That necessitates executing both sides fully. Very often, those are "business logic" branches that are very long, and you would only prefer to cover branch mispredict penalty.
Yes you would only do this for hot loops that have short basic block branches (binary search being the canonical example). That’s why I said hand annotate vs having the CPU try to detect and distinguish these situations at runtime.