Can the leader [direct] this attack?
In my experience, No. He didn't direct the D1F of the squad/half-squad now marked First fired, so, he cannot direct their subsequent fires.
eASLRB said:
A7.53 FIRE DIRECTION: A single leader cannot direct more than one weapon/unit per phase unless they are part of the same FG. Hence a squad that elects to use its inherent FP in a different attack than that of the MG it is manning does not get the leadership benefit if given to the MG instead. However, a leader can direct the fire of a MG as many times as the MG can fire, even if he also directed other units as part of a FG in the MG’s previous attack. Leader direction used during Defensive First Fire can be used again in Subsequent First Fire, FPF, or Final Fire, but again only for one firing unit/ SW or FG—and that unit/SW/FG can only include firers he directed during [his and their] First Fire; if forming a new FG or using a different SW during that Player Turn, the leader cannot direct its fire (even during FPF). Similarly, a leader may not affect more than one To Hit attempt per fire phase (except for a multiple ROF weapon) regardless of the number of SW the firing unit is eligible to fire. See also 9.4, 10.7, and D6.65.
The rule of thumb is that a Leader may omit units for his initial FG but may never add to unit to it.
But that doesn't apply here, because in your case the Leader does not begin directing
his initial FG until some elements of his initial FG have already fired without his direction.
That said, I
believe he may direct subsequent fires of units only if he also directed
their initial fire -- granted, the rule does not include the "
[his and their]" that I inserted above, but that's always how I've (mis?)read it and have seen it played.
I could be wrong. I'm thinking you
may have found a corner case I've missed. (That, or I cannot recall nor now find the rule that forbids your suggestion.)
Reading just A7.53, I'm kinda thinking your proposed use of Leader direction
might be
allowed. Clever.
Good Q, Jim.