Defender McCombe scored at the end of each half, his two goals sandwiched between a Wes Fletcher penalty and Josh Carson's late screamer, as the Minstermen made light work of their hosts, who played for most of the match with 10 men following Neal Trotman's 11th-minute sending-off.
"The one thing we knew about John is that, when the ball goes in the opposition's box, the ball is never far away from him," said Worthington.
"He has a wonderful knack of being around the ball in the box.
"It was a pleasing result; a great three points at a very, very tough place away from home.
"There was a lot of good passing football out there. We used the whole pitch, which was good, and it's nice to score as many goals as we have done. Probably, on a good day, we might have had another two or three."
City went ahead in the 12th minute when Argyle central defender Trotman brought down Ryan Bowman from behind as he shaped to shoot.
Referee Charles Breakspear immediately awarded a penalty before showing Trotman the red card. Fletcher sent goalkeeper Jake Cole the wrong way from the resulting spot-kick.
Argyle manager John Sheridan, Worthington's former Sheffield Wednesday team-mate, refused to blame his side's heavy defeat on the dismissal.
"I'm not making excuses," said Sheridan. "The sending-off made things tough, but I don't want to be beaten 4-0, even if it's with 10 men. We did look all over the place in the last 10 minutes.
"It's a shame because we've been on a good run of late. I told the lads that they all worked their socks off but it's not just about running around, it's about having a knowledge of the game."
The home side initially did well despite their numerical disadvantage with captain Conor Hourihane shooting just wide and Jason Banton bringing a good save out of goalkeeper Nick Pope
Their hopes of a second-half revival were dashed in first-half injury-time, though, when Bowman teed up McCombe to glance a header home from close range.
After Hourihane forced another save from Pope in the opening minutes of the second half, York made the most of their man advantage to dominate the match.
Only fine saves by Cole prevented Will Hayhurst or Michael Coulson from making it three before McCombe did just that as he stabbed home his second following a corner.
Carson rounded off the comprehensive victory a minute later with a magnificent long-range strike that inflicted a worst defeat of the season on sorry Plymouth.
Sheridan added: "It hurts because we know what we're trying to do and achieve so we've just got to bounce back. We won't hide."
- Sports & Recreation
- Neal Trotman