Don't underestimate the increased speed of a twin, and the associated reduction in think time for each step, all to be tackled as a new task.
When you start, you can't even keep ahead of a simple, 90mph aircraft. I can't imagine how terrifying and daunting it must be to learn ab initio in a twin. Probably why no flying training organisation, airline or air force appears to do it, or has ever done it.
QDM