It took a first-round pick in 2008 to find what would eventually be a solid-regular behind the plate in current catcher Jason Castro. Outside of Castro, who has admirably filled the defensive void left by Brad Ausmus' departure (as well as anyone could reasonably have been expected to, anyway), there's been a painful bust here (J.R. Towels), a backup getting more playing time than they deserve there (Humberto Quintero, Carlos Corporan), and a lot of "meh" down on the farm.
Max Stassi appeared, for a time, to perhaps be the answer at last. A prospect with pedigree, Stassi was taken by Oakland in the fourth round of the 2009 draft, falling out of the first round thanks only to a large signing bonus demand. No one questioned whether he had top-flight tools; he was expected to stick behind the plate, be an average hitter, and show above-average power for a backstop.
Following a solid season with the A's A-Advanced affiliate in 2012, the Astros convinced Oakland to part with Stassi as part of the first Jed Lowrie trade, and he immediately became the best catching prospect in the system. 2013 gave even more hope for a bright future, as Stassi posted a 139 wRC+ in 323 plate appearances in his first look at Double-A competition. He even impressed enough to earn a tiny cup of coffee with the Big League team at the end of the year.
Enter the 2014 season. Stassi began the year in Triple-A, and the wheels fell off. He managed just a 72 wRC+ with Oklahoma City, a bad number even for a catcher. 2015 was almost as bad, with a 73 wRC+ and a strike out rate that continued to trend in the wrong direction.
Stassi has power, there's no question about it. But the hit tool simply appears sub-standard at this point, even for a catcher. Strike outs look like they'll continue to be an issue, and he won't draw walks to help compensate. In a full season, a .300 OBP would be no small miracle. Any offense of note from Stassi will come from the occasional crushing of a mistake pitch.
Fortunately for Stassi, the Astros don't seem too concerned with catcher offense. There's been an increased focus in the organization under the new regime on framing, receiving, and throwing from behind the plate. Stassi does get good marks in those departments, enough to be a backup, at any rate. With Hank Conger off in Tampa Bay and no other obvious ready option anywhere in the system, much less on the 40-man roster, it appears that, as long as Stassi does his job as a catcher, he'll continue to have a job, regardless of how bad things get at the plate.