This thread is a good example of why I don't really contribute here anymore. Lot's of people with 1000s of post, claiming to be real pilots, who can't even read.
I found your initial question interesting, I don't know the answer either. I feel for you Breakthesilence, load of rubbish replies and insults. I salute you and am impressed that you managed not to sink into their levels. I probably would have, which is why I stay away, because every thread here tends to degenerate
As for the scenario, the question is "why do it?":
A 50 min flight is normally not planned much higher than FL300, so how much do you actually expect to gain comparing to flying at FL200? If in your scenario the home base has 3 runways and it's CAVOK, why not simply dip into the alternate fuel and complete the flight in FL200.