@petey_is_spidey: Nice breakdown but I was talking about the part when Superman was busy saving Lois. If he was as fast as Superman was in JL, he wouldn't get his arm chopped off, next thing we knew it might be his head for all we know.
And this goes without saying, how exactly does Superman hurt DD? Let's put aside the insinuation within the film that physical weapons could not harm him, and let's assume his "no-selling" durabilty is a 5.7 megaton nuke - as shown in BvS - and... IDK, his peak durability (at that point) to kill him was say, a 50 MT nuke (I just made that figure up, but I'm trying to prove a point). Since when could Superman dish out such damage????? Even if he could strike with the power of over 5 MT of tnt, and he delivered 1,000 of those punches per second, they won't hurt DD, since he'll simply absorb them.
Superman was also there when the nuke happened, just saying... It goes both ways. After all the Superman that DD stomped at the beginning just fought Batman and being exposed with a lot of kryptonite. Plus, he almost managed to BFR Doomsday if it weren't for the nuke, now that he has better control over his speed and not being exposed by kryptonite, it'd just be easier for him to do so.
Well in my opinion, that is.
If BFR is allowed, Superman could definitely BFR, especially since he knows how to use his speed now and doesn't simply bullrush. But I just think that if he decides to slug it out - even with his superior speed - he's in for a rude awakening.