^^^ good idea.
i think the downfall to most problems with full ups.. is the group isnt trying hard enough. every one needs to explode up. do some conditioning.. where you do show n go after show n go without a backspot.. this teaches the flier to really push off her bases and for the bases to just get the feel of pushing all the way up.
tell the main to extend fully, then flick her wrist at the top as hard as she can. and don't start spinning the flier before then.
tell the secondary to also extendfully, and watch the foot untill it comes all the way around.. don't throw the foot towards the main... because that could be disasterious. just push it up there.
tell the backspot to give it all she's got.. like everything, a lot of power from the butt, or ankles.. whichever she prefers.
and the flier needs to squeeze everything. expecially her ankles and legs together and don't force the spin.
most important i think though is the power.
also, practice makes perfect. it took me almost a year before i started hitting them constantly.. you really have to be aware of your body (as the main) be patient and don't give up on them.