Look at all the text that has been spilled for just a simple thing that could be explained adequately by "col(す)+row(い)=し". There is really not much point studying grammar if you don't know grammar first, much like studying bigfoot. People have strange hobbies, but we also have a ethical obligation to prevent young people from deluding themselves (and not sell them bigfoot nets) when it comes to topics that require a lot of time and energy.

In language learning you can run into a whole host of category errors and waste your time, learning words, grammar, culture, JLPT, hepburn, lingusistics, prosodic theory, an app, kanji instead of the language. It's a trap that obsessive people often fall into when they should have been listening to tapes until they can differentiate the sounds, match them to words and chatting with locals. Which is unfortunate since after learning the language these obsessive types could ace the JLPT no problem.