"Are these the same scientists that accept the "scientific" studies relating to secondhand smoke?"
No, they aren't the same scientists.
Intelligent Design is just as viable as ANY other theory regarding the origins of the universe. When matter and mass and gravity become infinite like the conditions at the time of the Big Bang mathematics breaks down and many variables become undefined, including time.
Who is to say that some giant alien creature named GOD didn't pick his nose and flick a booger which exploded into our timeline and universe?
My hypothesis can not be disproven so therefore it also stands as a theory. A theory is only good until it is disproven by counterexample or mathematical counter-proof.