The user could be frightened by the snail slowness of LaTeX2HTML to produce a reasonably sized documentation (let's say 50-100 pages). If the document is quite complex with many mathematical expressions and formulae, a running time of about ONE HOUR can be expected...
** HOWEVER **
This is only for the FIRST run of LaTeX2HTML.
In effect, the main part of the above mentionned hour is spent to produce the GIF version of the mathematical expressions and formulae (2 or 3 seconds for each). But once created, the software put them into files that are re-used for next executions. The translation is then MUCH more fast from the second execution (typically passing from one hour to five minutes).
The way this is done is quite mysterious, but this seems to be quite cleanly done: the existing GIF images are re-used without confusion when modifying not only the text, but also the sectionning, and even the number and content of the mathematical expressions. If a single mathematical formula or expression is added, a single GIF image generation will have to be done.