I've done something similar in saying that my issues were not encouraging so they were not something I wanted to talk about freely, but that I needed to sort out personally.
I tried that for a long time. But in almost every case they tried pushing until I would spill the beans since they always feel that they have an answer for any doubt. But we all know what their fallack mantra is don't we...more study....more meeting attendance......more field service. I can't count how many times I've got the "wait on jah" excuse.
Now when JW's get pushy with me I just find something in the immediate area interesting to me and head for it, sometimes while they're in mid-sentence. I've done that so many times now that my wife usually deals with any encounters we have with JW's trying to make sure they never get around to asking me anything.