In case every field in columns OD:Speed can have only a certain set of values determined by description, it is possible using data validation lists in all fields, and making those lists depending on selection in column Description. It doesn't ecxactly restrict the entry, but for columns you want to restrict entry there will be nothing allowed to enter (the data validation list will be empty).

Otherwise I don't see a way for this. VBA doesn't help, as there is no event fired on activating another cell (as much as I know).