I'm very new to Go, as is the friend who is both my rival and mentor. When the small group of us play, it's often a theme that there will be at least one, but often many cases where one person plays a nobi, that the response is another nobi. These are usually during the first few moves of the game, as none of us have strong joseki.
If someone's nobi makes their 2 stone chain adjacent to your 2 stone chain into a 3 stone chain, why should you just nobi into a 3 stone chain? How do you know when to stop the nobi?
can you post some diagrams?
See: Pushing from behind
Indeed, pushing from behind addresses this question adequately.
Two proverbs which apply in many of these positions are Hane at the Head of Two Stones and The one-point jump is never bad.
The hard part, of course, is knowing when they apply — if I could see that reliably, I'd be at least five stones stronger — but they are almost always worth thinking about.
Also the cardinal proverb, play away from thickness, to clarify my comment above. -Slarty