Pasta is a so-and-so. I think a lot of us find it we think we've got the ratio right for it, then when we're not looking the blood goes skyward. Pasta shouldn't be slow - it's not fatty in itself, but if the sauce is fatty and the cheese is ladled on then that is enough fat to really slow it down......
These days I save pasta for special occasions - too many variables to bolus for and be sure I'll get it right, sadly.
But I do know some T1's have got it cracked - bears of bigger brain than me, I fear.