Richnator,
I think all of us here on SDN can relate to your concerns in one way or another. For me, I have a habit of worrying about how other people perform, and this is nothing but pernicious. It is likely that there is going to be a huge variation between the overall---what's the word I'm looking for (someone help me out)----dedicataion maybe of those who take the time to sign in to SDN to give advice on studying. Realize that everyone is different. If studying for 2hrs and then napping has proved successful for you while studying stick with it. I studied for so many hours in one day only because I knew what I needed to do to be successful on the DAT. It is totally an individual matter. It certainly is disconcerning for some to see the frequent correlation between hours of studying and DAT scores among members of SDN, but don't think you must emulate this trend to be successful. Depending on how much time you have until the DAT, how comfortable you feel, and your overall feeling of the effectiveness of your current 2hr then nap study schedule, plan your study schedule accordingly. Studying for the DAT is a grueling process and EVERYONE on SDN will attest to this. It is boring (for most, but not some 😀) , and mentally exhausting. Just be aware of these common side-effects of studying and do not be afraid to step-up the pace of your studying a bit.
-Richard