BA TriStars were fitted with RHS tillers as an option. F/O's will have plenty of time to taxy when they upgrade. Also consider, a LARGE aircraft needs definate attention in order to not get a bogie off in the weeds. As the Captain is responsible, it is far better to have the F/O checking for vehicles and the taxy diagram. In addition, nearly all gate guideance systems are aligned with the LHS.