That makes sense to me. The shell is fundamental to the system, and is so heavily intertwined with readline that it is very sensitive to ABI/API changes. Consid

That makes sense to me. The shell is fundamental to the system, and is so heavily intertwined with readline that it is very sensitive to ABI/API changes. Consider: if you upgrade your readline without upgrading bash, or vice versa, you lose the ability to fix the problem even in single user mode. Having Bash control its own readline usage seems like the safest option, though conceptually a bit more complex.