That is a solid point you make there, I was thinking about that myself but I was hestitant to add that since I have no experience of that happening to me or to an other player. But if we do have cases where is this has happened because of the server and not the careless player then all the more reason to implement this.
At level 98 and 50% experience I thought to myself 'Alright, I must be careful and not mess up.' That thought was forgotten rather quickly because I was distracted, at the time I was chatting with 2 different people on the game, talking on skype and watching a football match. (a rather eventful football match) And dont get me wrong, I shared the story of my experience just to give an idea on how easy it is to make such a simple mistake that can waste so much time and how I came up with this idea, not to complain. Personally I have made peace with my mistake after a break of a couple of hours. But as you may have read, Starlight made an interesting point where people do lose the ability to evolve a pokémon because of a server crash and that is ragequit material.