When to use pointers?

[superbonzo]

Well, then you've learned something new because these words are commonly used about designs in general, but less so in the context of design of standards. In fact I don't think I've ever a heard a standard being called connected, brittle or monolithic, even though I suppose standards can be all of that.

I totally ignore what's your claim here ... yes, the STL is a standard but it's also a library design, so what's your logical point ??

You claim parametric scales better than subtype but you haven't explained how?

yes, but sice I want to avoid yet another flame war based on loose terminology and ambiguous problem statements, before explaning we should agree on what we're speaking about ... otherwise, it's just time wasted speaking of nothing. Anyway, your answer implies you don't agree on the problem formulation itself, so, I'm fine stopping here on this issue.

There is no special heap synchronization necessary if the default heap internally manages one heap per thread. Then threads aren't competing for a single heap, they all have their own.

but what happens if a thread tries to delete something new-ed by another thread ? in the worst case, you'll get UB ( for example, this is the case on winapi heap functions with synchornization turned off ), at best you'll get a performance degradation due to the inevitable synchronization. Note that not only the standard allows memory de/allocations between different thread, it also promotes them ( see for example the new exception_ptr specification ).