> It is not about being allowed at all. > They typically fail as devising such structure safely from low level code is a really hard problem. I took the phras

> It is not about being allowed at all. > They typically fail as devising such structure safely from low level code is a really hard problem. I took the phrase "being allowed to" as meaning "it is known to be safe to", in which case you seem to be agreeing with the parent (i.e. it's usually not allowed AKA it's usually not known to be safe).