Yea, this is one of those things where that argument gets tricky. On the flip side one could argue that diversification of implementations is key to the long-t

Yea, this is one of those things where that argument gets tricky. On the flip side one could argue that diversification of implementations is key to the long-term success of Bitcoin. If, let's say, there is a serious issue with bitcoind that shows up somewhere down the road that causes a fork and it is the only implementation everyone is using, there will be a network-wide problem. If there are a number of implementations in the wild, the fork would be contained to a smaller subset of users, and managed accordingly. Getting to this point of diversification safely is difficult, however, which is why I imagine some of the core devs might be against it. I remember Amir Taaki got a lot of flack when he came out with libbitcoin.