Just to chime in with some preference of mine, which adds nothing to the discussion, I use neither PARAMETERS nor LPARAMETERS, as I like to declare the parameters in the function definition, so in your case I would have done:
FUNCTION TestFunct(lVar1, lVar2)
or even better (for me!)
FUNCTION TestFunct(lVar1 as Boolean, lVar2 as Boolean) as Integer
The types have no other purpose than "documentation", and the parameters are LOCAL if you define them this way.
"The five senses obstruct or deform the apprehension of reality."
Jorge L. Borges?
"Premature optimization is the root of all evil in programming."
Donald Knuth, repeating C. A. R. Hoare
"To die for a religion is easier than to live it absolutely"
Jorge L. Borges