IMO, a lot of people like to blame everything on infections, but I don't know if an infection could cause gushing without producing off flavors/aromas. If the infection was producing CO2 to increase the foaming then it was fermenting and introducing its byproducts to the beer which would result in off flavors/aromas. Therefore, I am willing to say if the beer tastes/smells fine that it is a priming problem.
For you next batch I would recommend using 2 Coopers' priming tablets per bottle, and then do everything else as normal (except don't add priming syrup) and bottle. The Coopers product is very consistent, and if you have gushers then, we will need to discuss infections and off flavor identification.
Just my opinion