Considering I don't see any kind of encoder, they must be using a servo technique to manage position. They run to the end, reset, and keep track from there. This makes keeping track of motor pulses is critical. I have a printer that had behaved very well until yesterday. I had a print offset itself by 3" (75mm). I rebooted the printer, deleted all instances of the part file, and went through a lengthy diagnostics to ensure it was random. Everything seems okay again. As to overheating, the print just started, so that shouldn't be an issue; the environment is 20*C (70*F), so that is well within acceptable. There are printers that have quirks in this regard. Worst case was a printer that would print on the edge of the plate where every layer's max extent was at the edge of the plate. The whole print was "skewed". That tells me there is little confirming position other than pulse counting on the steppers.