queries on the practice of spunding practice

perfection

My queries
(i) Is spunding only carried out in a primary fermenter or can the operation be done in a conditioning tank too. Would the pressurized conditions affect conditioning operations in any way?
(ii) Assuming a brewery force carbonates its beers after filtration and prior to bottling in a serving tank, would a beer further carbonate in a conditioning tank beyond what gets naturally saturated in non-manipulated conditions? (is there enough yeast and fermentable sugars remaining?)
(iii) Do beers get their complete complement of CO2 by spunding or is a touch up of force carbonation required before bottling given that they may be subject to other operations in due course before bottling?
(iv) Overall, is spunding a popular practice in commercial breweries?
(v) Can ales too be successfully spunded?
(vi) If introduction of natural carbonation is desired in the secondary tank, can it be done by adding priming sugars (only) instead of actively fermenting wort (gyle) - are sugars usually enough to activate the lower concentration of yeast in the conditioning tank into a secondary fermentation?
Thank you