After some additional research, I can tell you that "inmersión" has not yet reached the English-speaking logicians studying recursive algorithms. Maybe you can try and push it onto them: define the term as José Luis Montaña does it: "La función g, más general, se llama función inmersora ..." and just go ahead and use it. If it doesn't work, you can say it was a good try.
I can imagine the primary objection to this will be that the term is already used to mean something else. Your counter-objection may be that it means something else in an unrelated area.
The established term for this (although I don't know how well established it is) is "generalization". It is a vague term, but apparently there is nothing better. It even appears in the writing by a Spaniard Manuel Rubio-Sánchez where he describes
exactly the same technique as mentioned in your syllabus: "Tail Recursive Programming by Applying Generalization"
http://portal.acm.org/ft_gateway.cfm?id=1822119&type=pdf&col...
Also, just in case, "recursive design" is busy with something else. Here it means "design of recursive algorithms".
The translation workplace 
peer agreement (net): +1
