I concede this point. The article was written from the perspective of a user who's running a high volume app and wants maximum control over how they communicate

I concede this point. The article was written from the perspective of a user who's running a high volume app and wants maximum control over how they communicate with foreign services (i.e. my perspective). I certainly don't want to dissuade companies from writing SDKs. They're great products and really help in getting people much needed traction as quickly as possible. For the GA of the new Heroku API we'll be shipping SDKs in as many languages as we can support!