Most people like to see sans growing together in a big pot-bunched together very full. Or just as one single perfect speciman plant as an example of that variety. The rizome's size should be large to promote growth and flowering. Separating the new sprouts will reduce rizome size and slow progress of plant growth.
If you want to remove the sprout and start another pot, that would be fine. If you want to leave it alone, that would be fine too. Sans don't need much light. Black coral will be darker in less light, brighter green in bright light. That seems to be the rule for most sans with leaf blades shaped like black coral--except moonshine, which is the opposite.
Take a look at glasshouseworks.com and check out their wide variety of sans. Interesting.
Johanna

Remove the offseets carefully, leave a 2" piece of rhizome. Peel off any bad leaves on the outside, then put into the pot, 6-8" round using fresh fast draining mix.
Tap the soil down by tapping hard on a cement step or potting bench. If they have roots you may water, if not wait until they do, which if its' hot may take only a few weeks, do not water until then, because they could rot. Put three offsets to a pot, they love to be crowded, and it will make a difference. Now they become young again, and may not flower for three years. You may want to finish off with a top gravel, to hold them and the soil in. If I left anything out will the rest of you please jump in. Remember they still need to be warm to do well, not below 55F some may be able to take lower temps, but I don't want to be responsible.