Witnesses do not decide ordering of units. Ordering is determined by the algorithm that looks back at the witnesses-authored units in the DAG.
What TPS limit do you expect to see in the real world (order of magnitude)?
You know, there is no architectural limit in the DAGs.
Regarding the practical limits, I don't buy into this race to Visa tps. The most pressing issue of crypto is not tps, it is adoption (which we address in the first place). Tps will come second after the first is solved.
I'm an adopter. I buy into this. What is currect [practical] TPS limit for Byteball?