You said it, not me. If the person showing the appreciation disregards the obvious conflict of interest, then that's a problem. If it were me applying to be a merit source, it would be obvious that I shouldn't give merits to those who were supporting my application in my thread. That's a bad use of merits; I would expect a potential merit source to know that; and I wouldn't support a candidate who did that.
I understand. Anyways, there is actually no restrictions to show some gratitude to those who show support in the application. I hope theymos and the others would understand that. By the way, thank you for your tip. 