I've made the statement a few times and was criticized for it, (and that's all good).. but, I still say it..not quite as you've put it Metalone..

...I think "sometimes" does fit into the equation depending on
what it is the dog needs to
fail in order to be taught...
Let's just take a dog who breaks from SIT while a gunner shoots a live flyer, a vocal dog at the line for example..I've just simply found it more productive to re-create the situation that triggers the undesireable deed, rather than rely on fate to finally obtain the opportunity to correct..i.e.,..
Set the dog up to fail in order to teach..
There are many things that if done correctly from the start, that would eliminate some of the tact..