I don't quite follow what is meant by 'out of season.' Would that be blooming a daffodil in mid-summer, or holding over to have daffodils at Thanksgiving?

The work of Dr. Miller at Cornell University is one of the most in-depth studies of bulb culture that I know, but they focus on optimal in-season bloom of daffodils, tulips and hyacinths in different zones in the U.S. rather than manipulating the normal bulb season.

What I've found to be the biggest problem with bulbs held here to late spring is that the buds blast when the weather warms. Soil temperature can be manipulated with mulch and shade, but I've not found a way to change the air temperature significantly in the garden.

Will overnight soaking of chilled bulbs rehydrate them sufficiently without causing rot? I didn't quite understand the question about potting soil and inground environment?

I haven't seen studies on how long a cooled bulb remains viable. I can hardly leave mine in the fridge long enough to have adequate chill. I'm always impatient to rush the season so we can move on to dahlias, glads and crinums in summer and sternbergias, oxblood lilies and acidanthera in fall.

Here is a link that might be useful: fall bulbs

The maximum time you can keep bulbs chilled varies from one cultivar to the next. Also, most of the work with bulb storage has been in the forcing trade, and some of the cold storage is potted rather than dry bulbs. According to the Holland Bulb Forcer's Guide, maximum Daffodil cold weeks time (a combination of both dry + potted storage) varies from 18 to 24 weeks. Keeping them chilled without potting them will probably reduce this number, but to what extent, I have no idea.

Foxesearth is definitely right about one thing: as the air temperature (and day length and sun's heat output) increases as you go from spring to summer, the bulbs' root systems will not be able to keep up with the transpiration needed to prevent early dormancy; the first part to go will be the bud, so if you try this, do it with the latest blooming varieties you can get.

Oh, and breaking dormancy is usually just a matter of increasing the temperature and making moisture available to the roots. The trick with dry cooled bulbs is that they should develop a root system before leafing out, and as the soil and air temperatures increase (at the time of planting), leaf and bud elongation tends to occur sooner.

Hmm. Definitely 'Hmm'

Planted into a near-dry mix in pots, and held in 'wine cellar' conditions. Judicious watering to get slow but reliable growth of roots. Morning sun later on. Possible. I clearly don't experience the rapid entry into summer that more continental locations do - and that could be a useful plus.

Thank you for all those very useful clues. Lots to think about and explore!

(I'm now wondering what there is about the Division 8 Narcissus that makes them first up and last away despite heat and such. Perhaps it's bulb size and the depth they they settle at. Plus being damp tolerant. Hmm...)