Hey , “the future-would-be legal eagle stuffed skirt” ! ( no offence gal :) .
I’m not conversant with the Contract Law but if you don’t understand the following it simply means that your english reading comprehension is floundering helplessly “in this case”.(still allow for “this”)
One doesn’t even have to necessarily be a legal frosh ( first-grader at law faculty) to get the picture.
In other words : Don’t make promises you can’t keep ( or you might be sued otherwise) That is my paraphrasing of the “promissory estoppel” in VERY GENERAL terms.
http://en.wikipedia.org/wiki/Promissory_estoppel#Promissory_estoppel
Hughes v. Metropolitan Railway Co
This bonus would be quite a light reading for you. It's free.
http://www.vuw.ac.nz/staff/dean_knight/Public_law_estoppel.pdf