In the early 1980s I was shooting color print film with a Konica TC and my favorite 35/2 Hexanon. The mercury battery just stopped working about half way through the roll. I knew the sunny 16 rule and I also had the handy sheet which came with the film. When the film was developed both halves of the roll were equally well exposed. I am using a hand held meter more now because none of my medium format SLR cameras have meter prisms (yet). If I shoot slide film I bracket more even though that uses up a lot more film, especially in the 6X7 format. With the lattitude of the color print film I can get good results even if my technique with the hand held meter isn't perfect. I have fun with the medium format cameras and I am not using them for fast action or long distance photograohy so speed isn't a problem.
I do not feel that that built in meters in my 35mm cameras make me lazy. Built in meters can be as useful and as accurate as separate meters. You just have to know how to use them. When I use my Canon F-1 cameras I try to meter a medium tone in the scene with the 12 degree spot meter. Then I recompose and shoot, without changing the settings. If I use a camera with center weighted metering like a Nikkormat FT2 or a Minolta X-700I use a different technique and I try not to let a bright sky influence the reading too much. I may tilt the camera downward a little and get a better meter reading that way. A built in meter is not some kind of crutch. It's a tool. If it's used properly it can help us get good results.