Playing at home, in front of an expectant crowd, will always bring pressure, but the former Wimbledon champion said he expects Murray to feel more relaxed than last year, when he held his nerve brilliantly to double his grand-slam tally.
"It is going to be amazing," McEnroe said. "To me there is a lot less pressure. No one can ever say to him: 'are you ever going to do it, how much pressure are you feeling?' He went through a lot to get that.
"I'm not saying there is not going to be pressure. I remember I had gone through so much turmoil that I said to myself that if I win it, I will never come back. Then the moment I won I thought, 'I want to come back'.
McEnroe lost in the final to Jimmy Connors when he defended his title in 1982 but achieved the double second time round when he followed up his 1983 victory with a stunning demolition of Connors in the 1984 final. Winning the title a second time, he said, was easier than breaking through.
"It is tougher to stay at the top than to get there in the first place but it just seemed easier to win that event again," he said. "But I thought I should have won it before I did.
"Some of it depends on how old you are and what you have been through. I am not going to say it is easier for him to win it a second time but there will be less pressure overall. He had a pretty favourable draw, he may have a tougher one, it may be more difficult. No matter which way you slice it, it is pretty tough to win it, but I think it will be quite a bit easier for him to do it."
As per tradition, Murray will open proceedings on Centre Court on Monday, an honour relatively few men in the Open Era have enjoyed. "There is always a feeling of an immense accomplishment," McEnroe said. "Superiority is not the right word but you feel the tradition of coming out at that time and playing [then] is different to other events. You have that brief moment of euphoria and then you have to accept the fact that now you have to go through the whole idea of possibly winning again."
The other big change for Murray this year will be the absence of Ivan Lendl in his corner, replaced by Amelie Mauresmo, the former world No.1 and Wimbledon champion.
The grass-court season is a trial period for Murray and Mauresmo, with a view to a longer-term arrangement and McEnroe, who expressed interest in the role but never received a call, thought it was a positive choice.
"I was hoping Andy would do something out of the ordinary, like he did when he started working with Ivan, rather than the same old, same old," he said. "And he's certainly accomplished that."
Mauresmo may only be 34 but she's already coached one Wimbledon champion in Marion Bartoli and Murray says he likes speaking to her and was taken with how considered she is.
Given all the fuss about a leading man hiring a woman as coach, it is to be hoped that the pair succeed but McEnroe said what happens in the short-term is not going to be down to Mauresmo, good or bad.
"A couple of times, I was asked [to be a coach] 15 or 20 years ago - when Boris [Becker] asked me to work with him and Sergi Bruguera had asked and I ended up coming more or less a week before the [US] Open," he said. "You can't do anything a week before [a grand slam] and expect to make any sort of change, when there's no way you can work with like the fitness. That's very difficult to walk into a situation like that."
McEnroe, who will again be commentating for BBC TV at Wimbledon and presenting 606 on Radio 5 live, was in the commentary box during last year's final and admits he was genuinely delighted that Murray finally made it across the line.
"I was pleased for him because I felt like he went through a lot," he said. "I watched this poor guy year after year having to deal with what people were hoping he would do.
"I like Novak a lot. I really believe he tries more than any of the top guys off the court to try to make things happen and he's trying to figure out ways to bring our sport up.
"They're all class acts, but he at least seems to make that attempt. But I was hoping Andy was going to win that. Novak's already won six of them. He's doing OK. So for Andy to win Wimbledon was good for tennis."