Issue was last time was it was when deepmine released if I remember correctly. A certain building at a high level had glitched stats which were super high. You had to purposefully not max it if I remember correctly. The issue wasn't as widespread and was far more likely to be done due to exploitation rather than a mistake. Some players will have bought crestplates when the issue was live by accident. Those who abused it obviously would be dealt with but the comparison is harder to make as the last issue was limited to players with large amounts of gold ready and you had to do a more specific set of actions to exploit it.