alot depends on the course and your personal preference; how strong are you? flat to gradual climbing allows for really either/or. in most cat. 4/5 criteriums, you'll notice that the speed consistency is terrible- slowish corners, then crazy sprints out of them every time, constantly gapping people towards the back. staying with the pack is really about staying at the front, and being able to take corners at speed with the fast guys. work on positioning within the group, so that you dont constantly have to work to stay on. some super fast crits will have you at LT for 80% of the race or more depending on the conditions. especially if you manage a breakaway.