re: Mars Sample Return - A Black Hole for NASA resources
Just ask the Soviets back in the 1970s and 1980s what working on a MSR of their own did to their other lunar and planetary programs.
http://www.astronautix.com/craft/mars5nm.htm
http://www.astronautix.com/craft/mars5m.htm
http://klabs.org/richcontent/Reports/mars/difficult_road_to_mars.pdf
http://www.marsinstitute.info/rd/faculty/dportree/rtr/rs14.html
