I know this is an old topic but I thought I could clarify some things as it pertains to rallying and being in/out of contact. I can illustrate this using the WINSPMBT scenario 41- Viet Village as an example (I know it's not WINSPWW2 but the subject pertains to both games). In that scenario the command structure is as follows.
A0- Battalion Commander
B0- Company Commander (commanded by A0)
B1
B2
C0- Platoon Commander (commanded by B0)
C1
C2
C3
D0- Platoon Commander (commanded by B0)
D1
D2
D3
E0- Platoon Commander (commanded by B0)
E1
E2
E3
Now say units B0, B1, E0, E1, and A0 advance on the enemy. Units B1 and E1 come under fire and are suppressed. (see pic below)
Note that unit A0 is just to the right of unit B0.
Now if we wish to rally unit E1 then note that units E0, B0, and A0 are well within range. The only units to be able to give an extra rally attempt to unit E1 would be his platoon commander, unit E0, and his company commander, unit B0. Unit A0 will not be able to provide an extra rally attempt to unit E1, nor would unit A0 be able to provide a rally attempt to any Cx, Dx, or any other Ex units.
If we wanted to rally unit B1 however, we find that the units able to give an extra rally attempt are units B0 and A0. Why can unit A0 provide a rally attempt to a Bx unit and not any of the other units? Well refer back to the pic of the HQ Menu.
We see that the Battalion Commander's commands are listed as B - Rifle Co VN. Now, see how this differs from the Company Commander in the pic below.
His commands are listed as C - Rifle Plt VN, D - Rifle Plt VN, and E - Rifle Plt VN. The long and short of this is that if a unit is not listed in the list of commands for a company commander or battalion commander then they can not provide a rally to said unit. Hence the fact that unit A0 could not provide a rally to unit E1 while they could provide one to unit B1 if they so desired.
Now, as far as being in contact to provide a rally attempt, it doesn't matter if the units involved have radios or not since the unit providing the rally must always be within 5 hexes of the unit they're trying to rally. The only thing radios are really good for, assuming you are using the full realism settings, is to call for support from an x0 unit and remain in contact with your higher commander at more than 5 or so hexes. Basically, if you are out of contact and you are an x0 unit then you will not be able to call for support fire and you will suffer some suppression. Any other unit out of contact will only suffer some suppression, that's basically it.
Hope all that can help any other players, new and old.