Great article! The only problem with it is examples. There are so many words that native speakers hardly ever use let alone non-native speakers. Исповедальня, барышня, стезя, кутья, шестерня... I just think it may put students off. If you used words that students might actually use your article would be priceless!

Ой май гад!!! Как хорошо, что я нейтив хд 

I accept your suggestion. As a exception of rule, the word мечтá has no genitive plural.

By the way, there is a funny story of a Soviet satirist Zoshchenko about confusing diclination of the word кочергá. http://ostrovok.de/old/classics/zoshchenko/story013.htm ;

Sorry, the presentation of this grammar topic is incorrect. The Genitive Plural is formed from the Nominative Singular ( ordered by the Nominative ending) regardless of the Gender. 

Great article! This indeed was one of the most challenging item I ran across in Russian grammar.

One item that helped me as a beginner (and advanced) student was when I ran across a 10-year-old Russian native speaker who made a mistake in her genitive plural (even though it was masculine). She said "этажов" instead of "этажей." Knowing that this was challenging for native speakers explained why it was so hard for me: it's not easy for anyone!