Playbooks

Read Option out of Shotgun Doubles Y-Flex is a zone-based run play built around a mesh point read between the QB and HB. The diagram shows the QB and HB crossing paths in the backfield with the offensive line executing a zone blocking scheme to the play side, leaving the QB to read the unblocked edge defender and decide whether to hand off or pull and keep. This is a straightforward run concept, not a play-action or RPO look based on what the art shows, and the primary read progression is the mesh point defender first, then the play side alley for cutback lanes.
Watch the edge defender assigned to the mesh point, if he crashes down on the handoff every time, the QB keep becomes the counter punch that gashes the defense. Check linebacker depth before the snap, stacked linebackers close to the line show run blitz intent and can beat the zone blocking scheme at the mesh point. Identify whether the defense is in a run heavy front with extra defenders in the box, since that numbers advantage on defense shuts down the zone run element of this play. Look for user controlled defenders flowing hard to one side post-snap, since a disciplined backside contain defender can blow up the QB keep read. Zone shells with safeties staying deep and not filling downhill give the offense a clean numbers advantage on the read option zone run.
Attack defenses that show light boxes or two high shells since the extra numbers in the box will slow down the read option mesh point.
Check the alignment of the edge defender pre-snap, if he is crashing hard down the line every play, keep the ball on the read more often to punish that aggression.
Pair this with Charger Cross or Double Slants from the same Doubles Y-Flex set so defenses cannot sit on run fits after seeing pre-snap motion or personnel.
Use Read Option on early downs in normal distance situations to keep defenses honest before dialing up HB Draw or Inside Zone from the same set later in the series.
Avoid calling this into stacked box looks with extra defenders showing blitz, since the numbers advantage disappears and the QB keep option becomes risky.