We've been doing the mototune breakin method on car engines for years and never had an issue. I always warm a fresh motor up to full operating temp (i.e. fans kick on) while varying the rpm slightly, then kill it and change the oil and filter right away (get out assembly lube, major filings or dusts, etc.). After that, warm it up fully and beat on it on the dyno, including both hard acceleration and deceleration (building rpm gradually). You can see oil smoke for the first few minutes (especially on looser motors), and as the breakin continues and the rings seat, the smoke goes away, pretty cool to watch the breakin actually occur. Then we'll change the oil and filter again, and put miles on it (if its a street vehicle). Changing oil and filter again at 500 and 1000 miles.