I've only actually tried this on my level 14 powertech that just got ion cylinder, but it deals a very small fraction of the damage stated in the tooltip, so little that there is really no discussion about either the tooltip or the ability being bugged. I'd like to see if this can be confirmed by other powertechs/vanguards.
A good way to test it is making sure ion cell/cylinder is on, putting pet on passive and just hitting the enemy with the basic blaster attack, the yellow numbers is the damage from ion cell/cylinder