Audsley (Volume 2, p668), alluding to tightly-fitting swell shutters in a small box, recommends the provision of "a small trunk or conveyance from [the swell box] to some adjoining room" to avoid the effect described above. I believe, however, that Audsley is sometimes regarded as a dilettante, not an expert.
On the other hand, I believe I read an account of another organ where, owing to tightly-fitting shutters, the Swell division could not be played without opening the shutters a fraction. I wonder was it Maurice Forsyth-Grant's book? Or perhaps I am imagining it?