Did you trust Gollum/Smeagol?

[Arwen1858]

The Ring seems to have been unable to achieve anything approaching this with anyone else save Boromir, who had a few months exposure to it (and understandable, if misguided, reasons as to why it might be in his, and more importantly his people's, interests to gain it).

Yes, but when it was near Boromir, circumstances were different. When Deagol found it, it had been lost for a long time, and would have been desperately trying to be found. So it would have been exerting its will very strongly. Whereas when Boromir was around it, it had already been found for a long time. It wouldn't have been as desperate as it was when Deagol found it and Smeagol felt it's pull.