The promotion through Television might create a negative impact on the growth of bitcoin. It's good to promote once we have made perfect solution to handle large volume of transactions without getting stuck to the network. The reason is that when promoting is done, surely we can expect a big number of users into the network which might cause a downfall because of transaction delay and minor issues associated with it.
Undoubtedly, the increase in active users and without advertising on television will slow down the speed of transactions, because the system has not yet been improved for this level of workload.