LeBron James, the best player in the NBA, sort of half joked that he could help the Cleveland Browns as a wide receiver, a position he was heavily recruited for when he went to college. Last year a local commercial showed him wearing a Browns jersey and it's certainly true that being a high-jumping 6'8", James has the skills and physique to be a Randy Moss-type receiver. Moss is a guy who can outjump and outreach anyone for a high pass, effectively giving his quarterback a place to throw to him where there is zero chance of an interception. At 265 pounds, James is no beanpole and he is one of the toughest guys out there on the floor, so he probably could withstand an NFL hit.
The Browns were quick to suggest that they could use James.
However he should say no. Here are some of the reasons:
Reason number 1: He's the greatest basketball player in the world. He has nothing to prove.
Reason number 2: He hasn't played football since high school. He could easily embarrass himself. Remember Michael Jordan struggling to hit .196 in double-A ball. Granted, Jordan's height was anything but an asset in Birmingham, since a 6'6" guy like Jordan has a correspondingly elongated strike zone, making it tougher for him to hit than most baseball players. But the point is that James could end up making a fool out of himself.
Reason number 3: There are no minor leagues in the NFL. Jordan at least got to make his try at a lower level (never getting past double-A or stepping onto the field in a White Sox uniform.) But LeBron, who hasn't played a down since high school would be stepping onto the field with the best in the game. Even guys who played four years of college football at top schools and starred there usually find that the NFL is a whole other world, and a much harder one.
Reason number 4: LeBron risks a serious injury. The NFL is about violent collisions between 250 and 350 pound guys running at full speed. And the ones that are out there know what to expect. Maybe he could take an NFL hit, but could his knees? It would be a stupid way to end a great career.
Reason number 5: The Cavaliers, especially with Shaq around (as much as he stays healthy, anyhow) to help LeBron defend inside, are capable of winning an NBA championship. The Browns are 1-8. They know that sending LeBron out there would put some butts in the seats and get some play on television, but that, and the fact that it would be tough to play much worse than the guys they have out there now, are the only reasons they're interested.
Reason number 6: Two-sport athletes generally don't pan out in at least one of them. We've already mentioned Jordan. Bo Jackson was the most genuinely two-sport athlete, starring both as a football player and as a baseball player, in fact being named to both the all star game in baseball and the pro bowl in football. However he suffered a career-ending hip injury playing football, and while he was able to restart his baseball career after undergoing a hip replacement he was never as good a player as he had been. Deion Sanders is another notable exception, but his stardom in both baseball and football led to conflicts with and between team owners over when he would play which sport. Sanders eventually gave up baseball and finished in the NFL.
Reason number 7: the problems listed above with football/baseball players would be exacerbated in the case of football/basketball. There is more overlap between the seasons and both sports are more physical than baseball (Yes, there are certainly some very physical collisions at home plate and high spikes and chin music and great catches while running into the wall and all the rest of it but overall if you play baseball don't have the constant pounding that you get in the NBA or the NFL. The only baseball players who get anything like the kind of heavy physical wear that basketball and football produce are catchers.)
Reason number 8: LeBron, you're too classy a guy to go pull a stupid stunt like that. Let Kobe do it.