It sounds to me like you're new.

1). BASE canopies, or any canopy for that matter, is not designed to be deployed with a mal above your head. Just because he used a BASE rig and canopy doesn't mean that cutting lines and then cutting the wing is a good idea. There's a video floating around of a BASE jumper who thought doing this would be a fun idea. His reserve handle got stuck and he ended up eating shit.

2) I'd genuinely interested in the school and instructor that taught an AFF 1 class that it's okay to cut it at 1000 ft, because that sounds like a load of shit. Every DZ I have visited, including spaceland, preaches a hard deck to AFF of a bare minimum of 2000 ft. Every skydiver I know doesn't have a hard deck below 2k. It's widely accepted that if you've got a mal at 1000 ft, get more fabric out. Sure, skyhooks and MARD systems are reliable, but nothing is guaranteed. So you go ahead and chop at 1500 like you claim, without a skyhook or MARD. Report back on how your landing and pants are.