And is not common is that this guy is on vacation? Recommendations of independence from hardware, designers must work directly with a network server, and only use their computers for backups. In addition, you can set a reminder (in iCal or other applications of your choice) at the end of each day to remind you to record your work in the same for everyone.
Blank or not used fibers
The developer did not expect that he would need a machete to take advantage of your file. He is still thicker than the Amazon rainforest, as your PSD has a huge number of layers, some of them with outstanding names "Layer 1 copy". Recommendations Imenuyte layers and create a folder when working in Photoshop. Of course, it requires discipline, but it's better than to return to the renamed or deleted segments. And yet, use the folder: They're there for a reason.