I've read most of the book and eat that way. It's how I've eaten for the last five years. It's not a lot of food if you break it into minimeals rather than thinking in terms of 3 regular meals plus two. Another thing to keep in mind is that Tosca Reno is a figure competitor and lifts weights like a bodybuilder for probably an hour a day, at least 4-5 days a week and probably does cardio at least 6 days a week. She needs to eat to fuel her activity level.
Even if you aren't doing workouts at that intensity level, eating 5 small meals is still an ideal way to fuel your body. Don't let yourself get ravenously hungry, don't let the blood sugar levels drop or create insulin spikes.
I don't nuke egg whites all day long
The real secret to eating this way is
PLANNING and cooking ahead. I cook a large pot of brown rice each weekend and put portions in small plastic bags and toss them in the freezer. Same with chicken breast. Cook a large batch, then freeze it in portions. Cut up your vegies ahead of time. Cook egg white/oatmeal pancakes in bulk, then freeze them individually so that you just need to nuke it and toss a few blueberries on top. Hardboil eggs ahead of time, then take them to work in plastic containers (in a cooler if you don't have access to a refrigerator!) Plan, plan,plan!
Mel