Ok dude.

To say that when someone says "4.3" they are obviously meaning "4.30 or lower" is stretching the vernacular to the breaking point. I think you'd be hard-pressed to find, for example, many (or even any) references on this board to a player or recruit running a 4.3 or 4.4 and have the poster meaning "4.30/4.40 or faster".
Besides, Ye Gods man, if your ceiling is an electronically timed 4.30 you're talking about an incredibly small number of people that have pulled that off regardless of position. Don't you think that's a bit of an unreasonable bar for comparison to be setting in the first place?
To be fair though, if it is your intent to claim that the NFL isn't exactly awash in 4.30 or faster running backs I totally agree. 
k: