The lower HT? My 30-year-old beater has an ovalized upper HT. There's no sign of collision damage, so I assume the HT ovalized from years of riding with a loose HS. ISTM that the upper HT is more likely to be damaged than the lower HT if the HS is too loose -- gravity will keep the lower race, bearings, and cups together, but the upper cup would "ride high" and tend to hammer the upper HT when the bike hits rough stuff.

In my case, I picked up some Loctite 680 and had a good LBS install a decent MTB cartridge HS with the Loctite holding the upper race in place. It has held up fine. So even if your HT did ovalize -- and I think we've collectively seen enough rough miles put on normal, rigid steel frames (especially cross and MTB) to suggest you don't need to worry about this if you keep your HS adjusted properly -- it's not the end of the world if it happens. So relax.