fishmanlee said:but why the "much like your father's" line in JEDI?
Because it's like (as in being a lightsabre) but not the same, he didn't say, "exactly like your father's", besides that observation would still stand if Luke's blade was blue, Vader's blade is red (or pink on the DVD's) and the hilt is completely different.
And that's telling because though both are Skywalkers and Jedi, Luke pulls back from temptation.