Look, it isn't working is it.
I mean, I do everything you say I should - slow down, ring my bell - and its not enough. Four times on my journey to Kingston and back I heard mutters about bikes.
In particular two of those complaints were that you "can't tell where the bell is coming from". Well, big hint: look behind you!
Yes I know you are busy nattering away and having a bell go off at random intervals probably does interupt your conversation, but two little points for you:
1) bikes are allowed on the Thames Path - it says so on a sign
2) biking is faster than walking - its one of the benefits
So you will be overtaken every now and then. If the whole slow down - ring bell - look behind - stop - work out which way to jump - start again routine is something that worries you then maybe you could make sure there is room for bikes to go by and not take up the whole path?
Then we wouldn't have to ring our bells and you could keep on talking without interuption.
Just a suggestion - its really up to you