Throttle pots - mechanical cable or directly mounted - have a sweep of resistance (voltage) outputs that tell the ECU what to do. Many ECUs are programmed to look at what range of voltage is being sent, and "learn" the range, but this can only happen within certain limits.
If the thottle pot has a "dead" spot at its lower (foot off) end, there could be a brief lag while the ECU deals with that situation. Voltage input and output from the throttle pot could be monitored on Lexia, I would hope, or metered.
In the absence of expected voltages from a thottle pot, the system might be substituting 'backup' values, to preserve idle speed, and allow driving. As Marc says, this may not constitute a major (limp mode/EML) fault.
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