I was always told that the first cross is not where you usually run into calving problems. The calves are fairly skinny coming out. I have heard horror stories of guys that have retained heifers off this cross, though. To answer your original question, I might think you would get docked on those smokey calves. I also have been told that Belgian Blues are fairly slow growing cattle.
Belgian Blues are medium sized, heavy cattle, sometimes with a massive double muscle structure. Their colors are blue, white, and blue and white. Belgian Blues are small boned with a sloping rump, hidden hips, strong legs and a relatively small head. They are quite robust and healthy.
Belgian Blues produce a cross bred steer with a high yielding carcass dressing out between 65 and 70 per cent. The meat is tender with a minimum coverage of fat with a high proportion of the valuable cuts.
The proportion of difficult births is particularly high among heifers.
I spent 3 months in Belgium back in 2000 and had a chance to visit a dairy farm there. The guy had a Blue on his Holsteins cows to sell the calves for meat ( he A.I.ed 4 or 5 of his best cows for replacements ) . He told me that he had to do about 40% C-sections on the mature cows. The double muscled calves looked great but not worth the trouble of all the C-sections for a long distance rancher. Very interesting visit, a lot smaller operation than most dairies here, only about 25 cows. The goverment limits how much livestock they can run on a hectare ( ~2.5 acres ).
We got 2 straws of Belgian Blue semen one year off a bull named Bacon. We bred him to one of our Fleckvieh simmental cows. The result was a not very tall very deep and extremely wide hairy bull. His adj. weanling weight was 880 lbs. We kept him to see what he would do and put him with our first calf heifers along with some other bulls. We came out with several bulls calves that we sold.(not cause they weren't good enough though) We had 5 heifers. We had one white speckled heifer that her coloring could have passed for a shorthorn, one red speckled heifer, one gray speckled heife, and one black heifer that had some specks on her stomach. After that year we sold the bull because of his heigth. We regret selling him to this day. All his calves have been very hairy. All of his calves were gentle. All of his calves grew great, had heavy weanling weights, milk good, raise great calves and we have never had to pull one calf related to him ever! I have never raised a purebred Belgian blue but that one experament truned out great. We have a full fleckvieh due to the same bull (Bacon) next spring.