Question on NFHS Formations

[Texas Aggie]

If an ineligible receiver is downfield on a forward pass that cross the LOS, then that's a penalty.

Under NCAA rules, this applies only when the ineligible by number or position is more than 3 yards beyond the LOS, and in practice doesn't apply to things like overthrown screen passes.

Neither does it apply on broken plays when a run play becomes a pass and the idiot line judge (on a 4 man crew) is too far downfield to judge whether the ineligibles were indeed downfield. [Actually, this isn't true; it was a play I missed early in my career and I figured I'd try to keep justifying it until they wrote it into the rules!!]