This has been puzzling me for the past few weeks of 1840. There have been any number of instances where one would think Gerard would have the ability to discern the truth about situations beyond an ordinary mortal's capacity, yet he hasn't displayed many powers other than giving Daphne bad dreams with his Celtic cross ... (e.g., he's unaware of Gabriel sneaking up behind him in an attempt on his life).
If it's the case of choosing to exercise his powers or not, Judah has had a seemingly curious lack of interest in using them ...
You're right Vlad and it doesn't make much sense either. For instance, in the times that he did use his powers, such as forcing Daphne to have those dreams to make her fall in love with him, his powers didn't seem appear to be all that strong or long lasting. Take for example the last spell he cast on her right before they were married, within a few minutes after the wedding, the spell wore off and she hated him!!!
IMO, he didn't seem to be all that powerful if he could only cast spells that lasted a mere few minutes. Why not cast a spell on her to make her love him for a lifetime? It seemed like he spent most of his time being a "normal" troublemaker (like Trask) instead of a powerful warlock.
I think the most powerful spells that he used was when he put Desmond under that choking spell & then again when he took Valerie/Angelique's powers away from her. That at least lasted for some time. But really, what else did he do? Perhaps being in someone else's body hampered his powers somewhat and he wasn't able to do the same things he could have done if he had his own body intact.
I noticed this because he seemed to be more powerful
before he possessed Gerard and was just the "head of Judah Zachary." He was able to control others more this way, making Desmond sign his name on a document, reading his journal, having Julia & Leticia try to re-attach his head to his body with that crazy experiment and so on.
Another factor that I thought of was love. The mere fact that he fell in love with Daphne (or at least claims he was in love) could have put a damper on his powers in the same way that Nicholas Blair faltered when he fell for Maggie.
Cassandra