Mr_OwlPretty sure it'd be tough to get the same level of spam out with two pockets. Either both soldiers are eating damage by standing close to the choke, or one soldier has to stand farther back and do less damage with his rockets. With a demo/soldier combo you have the point blank damage as well as the lobbed damage.
Its not like you would march through chokes together, at least I wouldn't if I was healing them. Buff both, push through choke with 1, then leap frog your soldiers constantly getting a fresh soldier in their face. Theoretically it seems like it would be effective.