"The standard of training just hit me for six in 2001 because every day was phenomenal," he said.
"You know you have got to be at your best every day or you will look like an idiot.
"It's something the new Lions will have to come to terms with and cherish in days.
"They will understand the level of player in the squad and realise they are at the same standard.
"It will drive home to them how good they are."
O'Driscoll is also confident the 44-man squad will strike up a swift understanding despite many of them lining up against each other just weeks ago during the Six Nations.
"Having experienced the Lions previously, I know that people gel very quickly," he added.
"When people go on a Lions tour they realise how big it is, especially going to New Zealand.
"I don't expect it to take long at all for us to come together, even though the Lions is such a different entity to anything else.
"It's unique in that you kick each other in the Six Nations and it's all forgotten when you come together and become Lions for two months."
The Lions skipper has great faith in the men he is leading this summer and believes they can create history.
"We have got a tremendous chance to go to New Zealand and be only the second Lions squad to win there.
"I look at our squad and see there is so much talent and style," he added in the Western Mail.
"There is the possibility we can play some fantastic rugby and, to my mind, there is absolutely no doubt we can go there and win.
"Certainly the key players in this squad are as good, if not better, than those in the 2001 squad."