The problem is that once you make an agreement, each "issue" is weighed against the value of being approved by Rome.
Is _____ worth splitting with Rome again?
Each incident is more inclined to be forgiven, rather than opt to go down that path of separation from Rome which everyone involved is far too familiar with.
Most people involved have experienced nothing other than ostracism from Rome for their whole Catholic (or priestly) lives.
The problem is this: We no longer have Archbishop Lefebvre among us. He was holy, wise and had great experience as a missionary. He knew what was important and what wasn't, and was prepared to make hard decisions.
If Bishop Williamson were in charge of the SSPX, I wouldn't be worried.
But, on the contrary, he is being RUN OUT of the SSPX -- which worries me greatly for the future and integrity of the SSPX.