[ExTxMarine]

The point is, can non-murdering Muslims ever join non-murdering Christians (and almost all are) in a march, and temporarily suspend their offense at depictions they don't like in the name of free speech rights?

The short answer is, "NO!" Because, non-murdering Muslims are as afraid of murdering Muslims, as much as non-murdering Christians, and as such, they will never speak against their own religion.

Long answer is, "Non-murdering Muslims are simply biding their time until they either become victims of the murdering Muslims, or join them."

[Laissez-faire capitalist]

You are free to believe what you will, but non-murdering Muslims are already calling out these lunatics who murdered people in France and thus would join that hypothetical march.

Secondly, there are Muslims who are quite Anglo-Saxon in appearance and would pass as a non-believer from any religion, or would pass as a Christian in that hypothetical march.

So what would be keeping non-murdering Muslims and Christians temporarily suspending their dislike for things that lampoon their own faith and then with that temporary suspension in place just march for free speech rights?