The Enhanced Editor was the original fix for the disappearing on-screen keyboard, but this can be taken care of by adding the site to the comparability list in the desktop version of IE. You can the choose the Standard Editor and have the ability to add new lines to your replies.
So far this combination is working for me.
Yep, just open with desktop IE and touch the compatibility icon in the address bar. No further action should be necessary after that.
I've got Compatibility mode and WYSIWYG selected and it works for me.