He made sure that his axle was long, his wheels far apart, and their spokes short, so that his chariot- bed was as low as possible.

He was right.
"But, after fighting from chariots was wholly a thing of the past in Italy and chariots were used, as they are used, for racing only, why cling to provisions for obsolete uses?
"A good general thinks of winning victories, not, like the fools I have disgracing me along the Rhine, of avoiding defeats.

So a good charioteer ought to think, not of avoiding upsets, but of winning races.

Yet all charioteers appear to want their vehicles as low built as possible, with short spoked wheels, wide apart on the ends of a long axle.

That makes them feel safer on a short turn, and, so help me Hercules, I hardly blame them, anyhow.