What do we do when an opponent's elite player goes down. and we want to trade for him? Let's use CMC as an example.
There are different ways of looking at this. First, what's your opponent's record? If they're sitting fairly comfortably (though 2-0 isn't exactly "comfortable," especially after losing their #1 pick), then it'll probably be tougher to pluck him from their hands. But if they're struggling--particularly if they have a near-desperation record like 2-4 or 3-5, where they need to be nearly flawless to reach the postseason--then obviously you've got leverage.
Also, you need to look at how long the player's out. If CMC's prognosis were 6-8 weeks, you can negotiate much easier with someone who's 0-2 than someone who's 2-0. 0-2 needs a couple wins over the next three weeks to still have a decent shot at the playoffs. Holding CMC vs. trading him for a top 12-16 WR that can help them win now clearly has appeal. But with a 2-4 week injury, good luck; I don't know many people who would trade an elite player for less than elite value, especially this early in the season, unless they believe the player will need a week or two to get back to 100%.
Then there's the schedule. Does the elite player have a bye during their absence? If the bye is later, after the player's expected to return, use that to your advantage in negotiations.
Also, is the backup rostered? In CMC's case, it might not make any sense to offer a trade until Mike Davis finds a home, because I can almost guarantee whoever has CMC is itching to get Davis, just in case CMC suffers a setback. And if they land Davis, they're less likely to part with CMC for anything less than pre-draft value.
This brings up process. How do you even offer a trade? Do you aim high and expect a back-and-forth? When it comes to elite players, don't count on it. If I receive an offer for my best guy, it better be reasonable, or there's no point countering.
That's why I always urge folks to start with a phone conversation or a message. No offers, period. Begin with a conversation. You want CMC. Who doesn't? So prop him up to your opponent. Of course he's elite. Sure, he got overworked last year, but he should be fine starting sometime in October. And yeah, there's a chance he could get shut down during the fantasy playoffs, because why would a non-playoff Carolina team risk serious injury to their franchise player?
But yes, you really want him. When healthy, and when starting, he'll be elite.
See where I'm going with this? Don't mask the fact that the player you want is great. Also acknowledge the risks--the same risks your opponent surely understands. This is an open conversation. You're sharing your thinking. And despite the risks, you're ready to pay a lot for him.
"How much?" might be what your opponent's thinking. I've been in many of these negotiations. As some of you know, I trade constantly--sometimes multiple times a week. When my opponent wants to know how much I'm willing to pay, we're about 75% done. There's mutual interest in making a deal. Now the only question is how far apart we are.
In the end, don't insult your opponent's intelligence, and don't waste their time. Everyone's sensitive about their elite players--particularly underperformers and injured guys whose values are lower than their future worth. Get inside their shoes. Identify what they probably need most, and how much they need it. Then start a conversation that makes clear you're trying to find something that helps both of you.