1. certainly it would break mactex. it could be fixed
by having mactex generate \%o3 instead of %o3. This
would probably mean talking about \\%o3, which prints as \%o3.
Should not be a big deal.
2. inchar came out as %I instead of %i. Quirk of having %I defined
as sqrt(-1). Maybe this will be fixed in the lower-case maxima..