Not too long ago, I played as Portugal except that instead of simply building an empire from Portugal, I sent my generals armies and ships ove to Ireland and Cagliari. From there, I made allies and then spent time helping them out by sending armies to the mainland. Since I think I play 1.0, I've rarely seen an amphibious invasion and I was able to safely help my allies without retaliation from my enemies.

Has anyone tried it also and gotten any interesting results or any variations or ideas?