the reason cubans get refused visit visas to canada is because 99% of the staff at the Canadian embassy are CUBANS!(ive been to the canadian embassy more times than what i can remember since i was 19) so,they know that all cubans have the right to (once in Canada) go to the US border and apply for Asylum(Cuban adjustment law)...trust me,,thats their main concern...you can count with your hand the cubans that have overstayed in canada in the past 10 years..
and its such a bull,,sometimes they approve old people(parents of canadians citizens or PR) even when ''like the rest of the cubans'' do not have travel history,,nor ''ties'' strong enough(like 10000 usd in the bank) so,its a really unfair system...i have a friend who worked at the embassy and you dont wanna know the way they treat trv apps...