This isn't correct. The constraints placed upon epitopes by the cell receptor vs antibodies aren't the same. Rhinoviruses and Influenza viruses escape past im

This isn't correct. The constraints placed upon epitopes by the cell receptor vs antibodies aren't the same. Rhinoviruses and Influenza viruses escape past immunity without fundamentally altering their biology all the time! The 2nd paper cited does in fact show functional virus with a charge-shifting E->K mutation in its receptor binding domain that escape many antibodies raised against earlier strains. I used to engineer viruses and human immune cells for a living - maybe read a little more virology/immunology.