There's also a word of warning here for the "bring on the CX" folks. There's a distinct possibility that you have an inaccurate idea of what Cross-Ex looks like, especially if you watch a lot of Law and Order. This isn't a court room, and it's especially not a TV court room. You aren't going to get them to admit to murder, or even that their plan is a bad idea. If you do your best "Sam Waterston Gets All Angry and Wins the Case" impression, you are probably just going to look like an ass.
That's not to say that CX doesn't matter. It's a great opportunity to make yourself seem smart and your opponents seem less smart. It's a great chance to point out over-tagged cards or over-claiming authors. You can poke some critical holes in your opponents position, and get them to concede links to your arguments. The problem is, all of that takes practice. You'll have to watch a lot of rounds before you can recognize a good CX question, much less ask one. Winning in Cross-ex comes from subtelty and strategy, not from yelling until you are blue in the face.
You'll have to do crawl before you can walk, so to speak. I think that most judges evaluate CX on a sort of "level" system like you'd see in an Role-playing game or a standardized test grading rubric. Different people would rank these behaviors differently, but I think that most students progress through these stages roughly in order
- Level 1 - Fills time: Is able to ask 3 minutes worth of questions that are relevant to the other team's arguments. Questions don't go anywhere strategically relevant, but is able to keep a conversation going.
- Level 2 - Fills holes: Uses most of CX time to fill in holes in their flow. Questions sound like "What was your third answer on the Spending disad?" and don't go any further. Shows that the student is at least making an honest attempt to flow, even if they don't have a complete picture of the round.
- Level 3 - Pokes holes: Uses CX to find flaws in specific cards/arguments, but not particularly important holes. Might spend an entire cross-ex drilling their opponent about how their Uniqueness evidence is "too old" from a few months ago, but when their speech rolls around their non-uniques are just as old.
- Level 4 - Link Fishing: Asks CX questions that establish links to positions they plan on running, but aren't terribly subtle about it. "So, uh, plan spends money, right?" Shows that they are at least thinking a little bit about using CX strategically, but also that their strategic considerations are shallow.
- Level 5 - Pokes deep holes: Asks questions that expose deeper flaws in their opponent's positions: necesary trade-offs, flawed assumptions, biases that cut along multiple pieces of evidence, etc. Also, their constructives/rebuttals actually use and impact those flaws.
- Level 6 - Link Harpooning: Uncovers links, but without being clumsy and obvious about it. Opponents/Judge might not know what links they are going for. Is able to use opponents' fear of linking into arg A to link them into arg B. Uses the Reverse Pit of Doom.
- Level 7 - Yomi: From the Japanese word for "reading," as in "reading the mind of the opponent. This debater is always one step ahead. Asks the questions that their opponents are most afraid of, exposes the links that they are most vulnerale to. Is focused on winning the round, not just the 3-minute CX time. Uses the Level 5/6 behaviors along with this "reading" to gain ground on the opponent.
This list isn't meant to be a step-by-step guide, more like a thermometer. A level 7 CX is evidence of a good debater. You can't just tell yourself "OK, I'm going to start asking smart, strategic questions" because you don't know what those questions are yet. Use this list to take your own temperature on occasion... are you stuck at Level 2? Did you miss an opportunity for a Level 5 question last round? Also, when debating/watching more experienced opponents, watch for their higher-level questions, and take note of them. Maybe even steal them when the opportunity arises. Like all parts of this activity, I think that learning to appreciate a good CX question goes hand-in-hand with being good at CX yourself.