C Gattman wrote:

* Runway Incursion – Any occurrence at an airport involving an
aircraft, vehicle, person, or object on the ground that creates a
collision hazard or results in a loss of separation with an aircraft
taking off, intending to take off, landing, or intending to land."


Actually, a "Runway Incursion" is defined as "Any occurrence at an aerodrome
involving the incorrect presence of an aircraft, vehicle or person on the
protected area of a surface designated for the landing and take-off of
aircraft."



I trust all of this has sufficient "probative value" to simply
reinforce my observation that two runway incursions were reported by
KTTD ATC to Seattle when a pedestrian (one) and an aircraft (two)
entered the Alpha Taxiway without clearance.


It doesn't.



As for what's on the FAA website, I haven't found an official
definition of "holding out", but don't let them catch you doing it.
You don't want to make all of your aeronautical decisions based solely
on what you read on the FAA website.


Or from what a CFI that's long on ego and short on knowledge posts on the
internet.