In Metaphors in Mind, Penny Tompkins and I originally listed ‘How far?’ among (what we called) the ‘specialised’ clean questions of David Grove (p. 283):

And how far {is} [symbol’s address]?

We observed David using this question on occasion and we have made use of it – although less and less over the years. We now consider ‘How far?’ to be a mildly leading question and have removed it from the summary of questions in the eBook version of Metaphors in Mind (due to be published shortly). The reason is that ‘far’ does not just presuppose a distance, it implies a large distance.

While the distance implied by ‘far’ will be relative and highly personal, we know from Elizabeth Loftus’ studies in the 1970s that how a question is framed can have a profound effect, not only what people answer but what they believe to be true.

You might think that a way to clean up a ‘far’ question would be to use the format of the ‘same or different?’ and ‘inside or outside?’ questions, i.e. to also give the opposite choice, in this case ‘near’:

Client: It’s starting to move towards me.

Facilitator: And when it’s starting to move towards you, how far or near is it?

This seems awkward and it doesn’t have that poetic rhythm so loved by David Grove. Simpler to just ask:

Facilitator: And whereabouts is it when it’s starting to move towards you?

The ‘How far?’ question becomes even more leading when asked with ‘could’ (a modal operator of possibility if I remember my NLP Meta Model correctly). The combination of ‘far’ and ‘could’ may well encourage the client’s attention in a direction it might not otherwise go. That’s fine if you are clear that is your outcome but not if you want to remain squeaky clean. 

The question can also be quite unproductive, as in this exchange:

Client: It comes out from my heart.

Facilitator: And how far could it come out from your heart?

Client: Well, it could come out a long way.

Facilitator: And how far is a long way?

Client: It could go a very long way, say to the end of the universe.

Facilitator: Ah, the end of the universe. And what kind of end of the universe is that?

Client: I don’t know. It could go that far but it doesn’t.

Probably no harm done, although the client may be a little exasperated. However after three questions the facilitator still doesn’t know if the client knows where it does come out to!  A cleaner question would be:

 And when it comes out, whereabout does it come out to?

To summarise, if the aim of the question is to invite the client to attend to the distance between perceiver and perceived, the ‘where/whereabouts?’ question will probably do the job more cleanly than ‘How far?’.