Yes, gridlock will affect a constitutional principle, although not necessarily badly. It's not necessarily worrisome.
The constitutional principle is that the government is responsible to the legislature. It is the core of parliamentary democracy. And when a government is not able to pursue a legislative agenda because it cannot command control of the legislative chamber, it must resign. We've believed that for centuries. It doesn't have to be that way, but that's the way it is.
When we get to two legislative chambers in gridlock, we're going to have governments that can't control the legislative agenda, and we're going to have to think differently about the principles of responsible government. I don't think that's a disaster. I think we could certainly work out principles of responsible government that coped with gridlock.
So in answer to your question, you bet it affects the constitutional principle. Does it affect it disastrously? I don't think so.