[TremendousJudge]

>or perhaps the problem is implicit allocations rather than value semantics

To me, this sounds like this is it. Explicit is better than implicit is a very useful truism

[cbsmith]

The counter argument to the "explicit is better than implicit" is that abstraction & encapsulation are such significant force multipliers. If done properly, implicit is good. It's just that in case of copying, doing it "properly" is well nigh impossible.

[kazinator]

          explicit  implicit

  good       *    <    *
 
             v    v    v

  bad        *    >    *

Good implicit is better than good explicit. (If all is good, go for implicit.)

Bad explicit is better than bad implicit. (If all is bad, go for explicit; don't hide bad explicit with bad implicit.)

Good explicit or implicit is better than bad explicit or implicit.