[tex-k] more el_gordo fun with METAFONT

[Karl Berry]

Knuth made the decision to not always check for arithmetic overflow (in
both TeX and MF), so I think these may be "known deficiencies that will
not be fixed". If you search around for overflow in *.web, you'll
see. E.g., lines 18407-8 of mf.web:
  Arithmetic overflow may go undetected; users aren't supposed to
  be monkeying around with really big values.

But I'll check with DRF et al. as usual. --thanks, karl.