I don't think that disney hold the honor of being the 'first' to start the trend, there have been loads, although they were possibly shown on tv first in america rather than straight to video as they were here.
Class of 1999 II, any sequel by Charlie Band, Whatever happened to Rosemary's Baby etc etc.
Also yeah people now say somethings shot on DV for stuff shot using digital cameras, just as people used to say films such as Bad Taste shot on 16mm were shot on Video, no, that would be the Violent **** Trilogy.
Also don't think that Disney kickstarted a trend, the trends always been there since video came about.
Tremors 3 & 4 are great too btw, (Class of 1999 II, was crappy but with an interesting twist)
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