Yes. I'm sorry about my use of the word 'powerful'. The usual interpretation of that word implies that more 'work' is being done. In this case its more about how fast that same 'work' is done. But as I said, if its accepted that the basic form of thermite is capable of melting steel, then its illogical to debate whether a more reactive version can do that same thing..
But if it reacts faster, then it just become an explosive, not an incendiary.
If something is DIFFERENT, then it's perfectly logical to ask how this difference will affect it's properties.
Consider bullets. A bullet from a .50 sniper rifle from is a lot faster and more powerful than a 9mm, vastly so, vastly more energy and destructive power. And yet for a specific job (shooting people underwater), the 9mm works a lot better
The .50 bullet just shatters.
So, something that is just "more" something does not mean it is better for a particular task.