I do it all the time and yes, It does change the tobacco IMO.
if you press a blend it will marry the flavors and make each puff more consistent which can be desirable or not depending on what you're going for, sometime you want to be able to pick out individual notes separately
It also squeezes out the oils and juices and saturates it similarly if you put a single ingredient in there like a straight virginia or straight burley, like if you want to make flake, you totally can with the noodle press but you have to press it at max pressure and for a good while.
I always have something pressing in mine, right now I have,
75% C&D Red Virginia ribbon
15% perique
10% C&D Espresso (which is a black cavendish with vanilla and coffee topping/flavoring)
Been pressing 4 days, going to leave it in 14 days and then date it and age it.
Have fun squishing stuff!