Most people I know forbid the use of virus bombs.. you have to remember, while 2nd edition was moving towards the game we have today, it still had a lot of its
RPG roots that had come through from Rogue Trader. You could seriously abuse the rules if you had a mind for it, and 2nd edition was much better if treated as an
RPG (or even historical-style game), rather than a competition sport; i.e you had to play with your opponent as well as against them.
However, the fact that you used to see Eldar Guardians suddenly 'polymorphing' into Imperial Assassins wearing terminator armour, riding a trike and then chucking vortex grenades, and armies of Wolf Guard terminators with cyclone-missile launchers, meant that obviously not everyone realised this
Starship Troopers was actually based on the rules that Andy had proposed for 3rd edition - the fact that
GW didn't want such a radical change to the rule-set was apparently the reason he left the company first time around and went to work on other stuff (and was probably the first in a long line of rules writers to follow suit after him).