^^^ You crazy guy.
I agree with you on most of that. I go over/over for as long as I can which covers the first few lifts of a heavy DL workout, then I alternate hands every two lifts. That's just me though. My workout buddy can hold onto more weight than he can DL with a double pronated grip which is crazy to me. To prove a point, he deadlifted 345 and then held onto it for 35 seconds before getting bored and letting go...and he can't DL much more than that. I think the key thing is what you mentioned...go as heavy as you can while being worry-free. Of course if you always switch your grip at some arbitrary number, then you won't train your grip as well as you could/should.