Anyone who thinks that given half a chance RU wouldn't completely destroy RL is kidding themselves. Signing Burgess would be a huge blow to RL in England, which is hanging by a thread financially, as yet again the message it sends is that RL is completely tiny compared to RU - it must be given that one of the biggest names in British RL, playing in supposedly the best RL competition in the world would jump to RU at the mere sniff of an opportunity to play for England. I wouldn't be at all surprised if the move for Burgess is because the RU surprisingly failed to get Sam Tomkins.
The only reason its not happening with Australian players in numbers is because the ARU is skint - if they had the money you can bet they'd be regularly poaching the NRL again. Comparisons to the old days when RL signed RU players are ridiculous, given that RL was offering supposedly amateur sportsmen the chance to make money from playing.
I'd also add that some ex-RL players are frankly a disgrace. Farrell earned a lot playing in SL, and was a very good player. There was even a grudging acceptance of him moving to RU when he was 30+ given what he'd given the game in England. Since then however, he's done nothing except hurt the game that made him a name worth poaching by RU. He's been directly responsible for several players jumping ship from his own club Wigan (Tomkins, Ashton), and no doubt indirectly involved in trying to tempt others in his role with England RU. Mike Ford is the Bath coach, and he had a long career in RL as well.
Again these guys will justify it as all being part of pro sport, but what they're basically saying is sod all the people involved in the game I used to play - fans, other players etc - its all about me and what I can get out of it.