SB Bw(X) can aid from behind only the same kind (i.e. grade) of bow, i.e. Bw(X).
This is the same for all SB Bow, they can aid from behind only the same grade of bow as themselves.
DB Bw(X) can be aided from behind by the element it is double based with (which is always Bw(O) or (S))
Please, let me retake this topic again. What would happen with a non compulsory double base of Bw(X)? The front element would be aided by the second when shooting. But would the front one receive rear support in close combat? According to page 7:
They fight frontally and receive and inflict the outcomes in close combat of Spears (O) if regular and of Spears (I) if irregular. If double-based with Bows, these provide rear support.
So it seems so, but other opinions would be appreciated.
On page 13 it says "Other troops... of the same type can be double based for convenience... but do not receive special factors ..."
IIMO rear support for double-based Bw(X) is a "special factor" as it is restricted to double based troops.
Similarly, a rear element of Bw(S) or (O) could NOT aid the shooting of the front element (and this is explicitly restricted to "required to be double-based" on page 34). A rear rank of Bw(X) could shoot over a front rank of Bw(X) as they are the same grade (and assuming the same kind of bow) and would be able to shoot over them even if single based.
By "non-compulsory" I assume you mean "not described as double based in the army list book" as there are some non-compulsory troop types that are double based if you take them, and some troops have the option to be different types and/or grades, including both single and double based options.
When (normally single based) troops are double-based "for convenience" and not because it is specified in the army list, then they fight
exactly the same as single based.
As they also have to have the same weapon,would this stop a rank of BOWS getting aid from a rank of CROSSBOWS,or vice versa?
IMHO yes.
I agree it, does stop bows and crossbows supporting each other.
