To run an old document faster, and use the new features of
LaTeX2e, you should try using <#658#>LaTeX2e<#547#><#547#> native mode<#658#>.
This is done by replacing the command:
373<<#549#>options<#549#>>374<<#550#>packages<#550#>>375{<<#551#>class<#551#>>}
with:
376[<<#554#>options<#554#>>]{<<#555#>class<#555#>>}
377<<#556#>packages<#556#>>378
However, some documents which can be processed in LaTeX~2.09
compatibility mode may not work in native mode. Some LaTeX~2.09
packages will only work with LaTeX2e<#558#><#558#> in 2.09 compatibility mode.
Some documents will cause errors because of LaTeX2e's improved error
detection abilities.
But most LaTeX~2.09 documents can be processed by LaTeX2e<#559#><#559#>'s native
mode with the above change. Again, the easiest way to find out
whether your documents can be processed in native mode is to try it!