Invisible extended length at front of train
Some train engines apparently have extra size in from of train that is invisible, causing train to brake before red signals earlier than normal.
CHAMELEON class engines have been affected since their first introduction.
MEDIUM/FAST class Maglev engines have had this problem introduced sometime in the v0.8.x series of releases.
This effectively makes tight fail-safe high-speed merging mechanisms fail and causes a train to brake briefly before a red two-way entry signal when it shouldn't.