To eliminate those kind of things we do a few things. For the whole Houston/Texas community we have a mock kickoff in December (should be the 14th this year) that walks teams through the engineering design process. For our team in particular we make sure that everyone has seen a lot of match video before we even get close to kickoff. We also meet the Thursday and Friday before kickoff to do last minute preparations and go over our design strategy with everyone.
This year we are trying something new in the fall to get younger students up to speed. Our plan is to do a full FRC build but stretched over three months. We are building for our
mock game. The idea being it should give us more time to really work through problems and do a lot more teaching. Also the robot will never compete so it's okay if it doesn't get finished or if it isn't perfect (it also probably won't be painted and no practice robot). This will be happening concurrently with our veteran students building for VEX Toss Up and also acting as teachers when the younger students run into problems during the build. We have two new mentors to train as well so they will be heavily involved in this process too.