The Washington Capitals are 47 games into this NHL season, but as shown in their latest loss Wednesday night to the Eastern Conference-leading Pittsburgh Penguins , they have yet to identify any type of winning formula. Uncertainties about the roster’s configuration and strength have lingered for months, and they remain as prominent and problematic as ever as the Capitals continue to show a persistent ability to self-destruct. Following the 4-3 loss to Pittsburgh, the middling Capitals are 4-5-5 in their past 14 games and fighting to stay afloat as the schedule grows increasingly packed with important games. The shootout success that helped earn victories and points early in the season — Washington went 8 for 11 in shootouts to start the year — has dried up, leaving little to mask the fact that the Capitals have a .414 winning percentage in games decided in regulation, eighth worst in the league. And that puts a spotlight on the imperfections that prevent Washington from finding ways to succeed.