When I got the first issue of this arc "Powerless", I was a little underwhelmed, to be honest. I felt that Brubaker was going down the same road that Grant Morrison had taken after a while of doing Batman, and he decided to completely go off the rails on that with throwbacks to garbage Silver-Age stories. After reading the second issue, I finally understood. It wasn't so much that Brubaker was trying to bring things like Madbombs (an old 70's Maguffin) back into regular Cap continuity: He and the great Alan Davis were paying homage to some of the wilder adventures that Cap got into during the 70's era Cap stories.
I felt that Brubaker wanted to lay off the really heavy stuff that had defined his run and have a little more fun with Cap since he's transferred the heavier and more espionage-related storytelling to WINTER SOLDIER. Davis's work here is spectacular in his very singular style. The tale, involving Hydra, Codename Bravo, and members of the Serpent Society is basically to cause chaos with the main intent being the undermining of Steve Rogers' faith in his country. The less faith he has in his country, the less faith he has in himself. The less faith he has in himself, the more likely that he will lose his physical strength. To that end, Hydra has The Serpent Society setting off Madbombs, and they do just what it sounds like they do, and Cap, The Falcon, Hawkeye and Sharon Carter throw themselves into the fray and Cap does indeed lose his abilities.
While the investigation into exactly how this happened goes on, Sharon Carter is onboard the Quincarrier and is forced to confront Machinesmith and his abilities to take control of all the machines on the ship. This is actually the best issue of this arc as Sharon once again, under Brubaker's watchful eye, shows that she's as capable and independent and strong as any of her male counterparts, if not more so. When is Sharon going to get her own comic?
As things come to a close, we see Cap and Hawkeye fight a Madbombed Falcon and a frenzied crowd, not to mention Codename Bravo.
I'm not sure where Brubaker is leading all of this, but it was a really entertaining wink to 70's era Cap and Falcon stories packed with great Alan Davis art.