Early in the veteran left-hander's North Side tenure, the answer appears to be a resounding "yes and yes."
When the Cubs acquired Hamels from the Texas Rangers before the non-waiver trade deadline, their rotation was in trouble. Yu Darvish, their $126 million man, had an ugly 4.95 ERA and was dealing with triceps and elbow issues that would eventually cost him his season.
Neither Jon Lester nor Jose Quintana was pitching like a top-shelf starter. Tyler Chatwood was battling command problems. Overall, Cubs pitchers posted a 4.56 ERA in July.
Chicago was hoping Hamels would be the cavalry as it battled for supremacy in the National League Central and aimed for another deep postseason run. But there was no guarantee.
Hamels has an ace's resume, with four All-Star appearances and four top-10 Cy Young Award finishes. He owns a 3.48 ERA across 98.1 playoff innings and won a ring with the Philadelphia Phillies in 2008.
Lately, though, he's been less a reliable stud and more of a payroll drag. In 2017, the Rangers paid him $23.5 million, part of a $144 million extension he signed with Philadelphia in 2012. For that lofty sum, Hamels gave Texas a 4.20 ERA and career-low 6.4 strikeouts per nine innings.
He turned 34 in December. It was worth wondering if his career was on an irreversible downslope.
This season with the Rangers, he posted a 4.72 ERA with 114 strikeouts in 114.1 innings. Despite a rough July in which he coughed up 21 earned runs in 17 frames, it was enough to entice the Cubs to send a couple of minor league arms and a player to be named later to Texas in a change-of-scenery swap.
So far, Hamels has been a revelation. In six starts with Chicago, he's 4-0 with an 0.69 ERA. The opportunity to pitch for a winner in the heat of a pennant race has brought out his best.
"To be able to change kind of the mindset, now to go on a first-place team, there's something inside of you that sparks when you get in those situations," he told reporters at the time of the trade.
Hamels' average fastball has clocked in at 92.7 mph this season, per FanGraphs, a tick above his career mark of 92.3 mph. But he's throwing it just 26.8 percent of the time compared to a career average of 39.2 percent and relying more on his off-speed offerings.
Here he is authoring a complete game August 23 against the Cincinnati Reds and throwing like a guy you'd gladly hand the ball to under the bright October lights:
Most essentially, he's given the Cubs a necessary ingredient to wrest control of the division and get back to the Fall Classic.
"He has all the credentials," first baseman Anthony Rizzo said, per ESPN.com's Jesse Rogers. "And he seems like he's having a good time."
Hamels has a $20 million team option for next season, with an innings-based $24 million vesting option that he's unlikely to qualify for and a $6 million buyout.
The Cubs probably won't pull the trigger at $20 million, but Hamels has pitched well enough to earn a lucrative deal this winter, in Chicago or somewhere else.
We're in small-sample territory, admittedly. No one expects Hamels to maintain a sub-1.00 ERA over the long haul. But he's not that far removed from success, either. He was an All-Star who eclipsed 200 innings as recently as 2016.
Now, he's turning back the clock.
The Cubbies needed him. He needed the Cubbies. Sometimes, these things just work out.