"When you look at the sides and you look at history, that's an easy suggestion to make, but they're all tough," Deans said.
"The fact of the matter is once you get into the tournament, there's no such thing as an easy draw."
He said it was early days to be making judgments about teams' World Cup chances.
"We've seen in recent times Test match rugby is about in-the-now, it's about on-the-day, and nothing that's happened before has any relevance on what's coming after, so we (have) just got to keep working our way through the program," Deans said.
Flanker David Pocock was also present for Monday's draw in London and toed the same line, while admitting England's Cup host status would give them an added edge.
"As Robbie said, there's going to be no easy games and, to win the tournament, you have to beat the best and deal with what you're dealt," said Pocock.
However, the 23-year old added that England go into the tournament with an edge as host nation.
England coach Stuart Lancaster called it "fate" that his side drew a pool with Australia and Wales.
"It's a pretty tough pool," said Lancaster. "Wales, I've got a huge amount of respect for what they've done recently.
"Australia have just beaten us and are an incredibly competitive nation. We'll look forward to it in a few years' time," added Lancaster, bidding to follow Clive Woodward, the man behind England's 2003 Webb Ellis Trophy triumph.
Pool B brings together seeds South Africa, Samoa and Scotland.
Top-ranked New Zealand headline Pool C along with Argentina and Tonga while, in Pool D, the top teams are France, Ireland and Italy.
The quarter-final draw could put New Zealand up against France - who knocked them out in the last eight in 2007 and met them in the 2011 final - or Ireland.
Meanwhile the winners of England, Australia or Wales will face the runners-up from Pool B who, on current form, are likely to be Samoa or Scotland.
Whoever wins Pool A will avoid New Zealand until the final provided the All Blacks, as they've done at every previous World Cup, win their group.
The Pool B winners will meet the runners-up from Pool A with the winners of Pool D, where France will be the favourites, facing the runners-up from Pool C, likely to be Argentina or Tonga.
The 2015 World Cup in England, the eighth edition of the tournament, will run from September 18 to October 31, 2015, with the final at Twickenham.
-AAP