There is a way to do formation takeoff and landing, and I'm sure those guys were properly briefed, and probably owned a FAST card.
With the Skytypers we used to take off 5 aircrafts, 3 in a vic, 3 secs, 2 abreast. We landed all 5 stagered. Be we had non standard methods.
At any rate, and I'm not blaming either of those pilots, when you land the lead is usually landing long and keeps rolling fast, just to try to avoid what happened there.
I think the formation flying card calls for landing on the centerline one behind the other, then "call right" once you have your speed under control to let the other guys know they have room for mistakes on the centerline/left side of the runway.
Formation takeoff/landing is not to blame, and probably the most exciting part of flying at an airshow. It is nevertheless a display of skills, and from experience, there is no worst feeling than flying in formation with people you don't know/trust.