Ironically, it says this as a bad thing, but in an ideal world this would be 100%.
It would be like saying "2/3rds of coders have reviewed their colleague's code and found bugs". Since bugs are basically unavoidable, the fact that 1/3 haven't found any points more in the direction that they're not looking hard enough.
edit: pretty much everyone seems to have taken this the opposite way to how I intended it, but re-reading I can't figure out why that is the case. I'll try to re-phrase:
Science cannot be perfect every time. It's just too complex. This is why you need thorough peer review including reproduction. But if that peer review/reproduction is thorough, then it's going to find problems. When the system is working well, basically everyone will have at some point found a problem in something they are reproducing. This is good because that problem can then be fixed and it will become reproducible or be withdrawn. The current situation is that people don't even look for the problems and no-one can trust results.
edited again to change "peer-reviewed" -> "peer-reviewed including reproduction"