Crawling along the second line.

I find it amazing how often we ignore basic common sense. In go these are somewhat formalised into the canonical 'go proverbs'. One such proverb is about crawling along the second line (i.e. it;s a bad idea). What this boils down to are two points: It is inefficient: It gives away influence.
The game above illustrates both point well. Black has invaded against white's D16 opening position. The line white selects lives easily enough but black presses white down into the side, gaining liberties and strength in the process- this has given white c7 solid points of territory, in exchange for black entire area below: it is inefficient in terms of score.
The ramifications of this lead on the next point- influence- black becomes really strong in his enemy's area of play, the crawling gives black a solid wall to build a base deep inside what should have rightfully been a white dominated region. Some players refer to this strategy as 'the knife in his guts' meaning the wall of stones tears the opponent up from within. In this game we can see how black's formation eventually captures the outlying white stones above it (toward the centre) achieving a far greater localised score than white's invasion response. The stones marked with a triangle are dead. Black wins by resignation.
What I find interesting in these scenarios is that the players are competing for the ability to develop faster. As we see, white's tactic of solid territory grabbing by crawling is useless in the long term. The advantage is both oblique and subtle, ones tactic for gaining the development advantage must be weighed against a mental model of the opponents (which may be unreliable as it is a educated guess). This is where the proverbs can be used to guide the player- in recognition of a bad position and formulation of a way out of it.