does spiking always mean ability to bloom?
 

Given that a plant receives ideal culture, does production of a spike / sheath always indicate that the plant is able to bloom? Or do immature plants sometime produce spikes without flowers, or buds that never open?

Aside from Catts that sometimes make empty sheaths if they're not strong enough to bloom, I think all other plants that spike will bloom. If a plant has the energy to send up a spike it will have buds, or else growing the spike was pointless for the plant. It's just the bloom count that will be different. A first time bloomer will have a lot less buds than when it's fully mature. For example, I got a young Onc intergeneric 2 years ago. First blooming only gave 3 buds on the spike. It's going to bloom aain for the third time since then, and this time the spikes have 9 buds each.