3.13 Reexamined

[saracv3]

A unit may only be enhanced by one leader, and a leader may only enhance 1 unit.

Yes, that I see, but my question is two leaders  in adjacent  hexes, one higher rank leader w/ a +1 or +2 modifier on top of a unit(s) and the adj. hex lower rank on top of a unit(s) that has a +1 modifier.

In the previous ex., we have a 16 direct fire attack: Col. +2 mod. w/ 8 df 75rcl and adjacent +1 Cap. w/ 5 df  MG Total = 16 (Yes, 9 rated HMG in diagram.) This is more for 6.41 than 6.42, but I've always thought it was possible to combine adjacent subordinate into one attack.