It is not uncommon for patent applications to relate to "systems" comprising subject matter relating to more than one examination art unit and/or classification.
Consider a self-driving car patent application that discloses novel steering and/or braking control methods based on novel analysis of sensor (e.g. LIDAR) data, e.g. with claim:
A method for automatically decreasing stopping distance of a vehicle, comprising: (a) projecting a structured light pattern from the vehicle; (b) detecting a non-transient obstacle external to the vehicle; (c) automatically pulsating brakes at an increasing duty cycle; and (d) automatically oscillating steering about a stopping axis.
In this case, there could be in-depth technical details relating to both vehicle control and wireless sensing. However, it is unlikely an examiner would be proficient in both these technical areas (if not for this example, then at least for more complicated examples).
Do examiners just "do their best" despite potentially not being able to apply appropriate obviousness and/or enablement arguments, and probably performing a poor search? If so, are these types of patents more vulnerable to invalidity challenges due to weak examination?
EDIT: Thank you for the answers so far, though they appear to focus on the "easiness"/difficulty of an art unit. The question here is how to deal with a case where an examiner is not technically equipped (i.e. cannot represent and/or play the part of a PHOSITA) for at least one of the technologies he/she is examining.
