This discussion reminds me on how much "The Infantry Section and Platoon in Battle" needs to be updated.
Do not get wrapped around numbers, as they never survive first contact.
For example, A TO&E Infantry Platoon has 39 soldiers (40 with att medic).
HQ Section:
- Pl Comd
- Pl 2IC
- LAV Sgt (or HQ Sect Comd if you will)
- Wpns Det Comd (or HQ Sect 2IC if you will)
- Driver
- Gunner
- Signaller
- 2 x Wpns Crew (for whatever you want to deploy)
- (add the medic and this gives you 10 in HQ)
Rifle Sections x 3
- 10 troops as previously detailed
Now, with TO&E laid out, we now have to recognize that a Rifle Platoon will never operate as such. First, the 2IC is not going to ride in the HQ car. He will usually head to whatever car is in depth (usually Charlie by default, but never assume so as rotation is necessary). He may take the medic with him to enable him to immediately fire up a CCP - if so, your bouncing two pers out of a section. One school of thought sees the LAV Sgt not crew commanding the HQ car, but rather the lead car (usually Alpha by default, but never assume so as rotation is necessary) so now we have crew commanders bouncing about. Add in some specialist assets that need a lift, and now you have some LOB, or at very least, some dudes in a small det riding in another organizations car (I've seen this done with Engineers).
As well, we are moving towards 2 x DP2B (PLQ Inf) pers per section - in effect giving a MCpl in the Crew Commanders seat and a MCpl dismounting with the Section Comd. When a Mech Platoon is away from its cars, this may very well set the Section Commander up for the "2 Groups commanded by MCpls" idea that was referred to above (and that we see in the US Military), leaving a lone fireteam partner for the Section Commander so he can put his Fireteam where he wants.
All this goes that TO&E only acts as a manning guideline. Again, it never survives first contact and flexibility is key.