so after a flower wilts and i pick off the old stem, a new spike will never grow out of that plant again..?? will it grow new leaves and then re-spike or just grow new leaves..??
The old stem won't grow anything more but, as long as it is looking healthy, it is helping to sustain new fan growth for the plant. It probably will turn brown eventually and at repotting time you might want to cut it off.
That existing growth or fan is done. It won't bloom again, and it won't grow anymore leaves from the top. The new growth coming up from the bottom should bloom after it matures. As the plant gets older and larger you will start to get multiple new growths and as they mature multiple spikes. These are plants that truly get better with age.