That has the same in-band problems as existing specs, which is that things generating the data need to have that callout. There are many cases where the "solut

That has the same in-band problems as existing specs, which is that things generating the data need to have that callout. There are many cases where the "solution" to the CSV inband signalling problem was to just reject values with commas, because they should never come in and if they ever do they should be investigated because they weren't valid data for whatever the CSV was storing. The whole problem is that programmers don't think to do that. The siren call of the string append function is just too strong, especially when programmers don't even realize they should be resisting.