Marginal Analysis and Language Acquisition

This falls in the studies I would do if I were omniscient category.  If you dont like studies you can gut this pseudo-one by simply reading the sentences that end in a question mark (?).

When learning a language there is a lot with which you can preoccupy yourself.  And depending on your ultimate goals, there are many ways you can measure your level of success.  Here are some rough thoughts on the topic; I’m open for suggestions.

Lets assume my ultimate goal in learning Spanish is to be able to communicate verbally (rather than in writing or with grammatical precision or to have a perfect accent…),  I am interested in the quickest route to this goal and am trying to consider where my time is best spent.

In the process of reaching this goal there are many obstacles; we will just take one to keep the analysis simple.  For example, in Spanish nouns have a gender (an aspect of the language that is completely foreign to me and that will require lots of time to learn).

A shortlist of things I must consider:

• Time it would take me to memorize the gender of nouns from a book.
• Number of nouns needed for an ample and sufficient intermediate vocabulary.
• Frequency I could learn the gender of a noun in a spoken conversation.
• Percent of nouns someone wouldnt understand if I guessed the wrong gender.
• Rates of noun acquisition at different levels of language ability
• ...

My question is: is it even necessary that I study the gender of nouns?  If my ultimate goal is to be able to communicate verbally and the costs of learning the gender of these nouns formally (through study) are much higher than the costs of learning them informally (through conversation), why bother?

Perceived costs of not learning the gender of nouns formally:

• Grammatical mistakes
• Time spent learning suboptimal vocabulary
• Minor confusions from time to time
• Loss of grammar-freak friends (could also be a benefit)

Perceived benefits of not learning the gender of nouns formally:

• More time in conversation
• Time spent learning the more applicable nouns to the standard vocabulary
• Better develop Spanish language intuition
• Quicker ascent to greater comprehension in conversation, which in turn would lead to a greater noun-gender acquisition.
• ...

What other things am I wasting my time studying that could more easily be acquired through action?