Requirements to Play Jessie & James

[Otaku]

Jessie & James
Trainer — Supporter

Each player discards 2 cards from their hand. Your opponent discards first.

You may play only 1 Supporter card during your turn (before your attack).

1. Can I still play Jessie & James if one player has no cards in hand to discard?
2. Can I still play Jessie & James if one or both players can only discard one card for its effect?

The way the text reads, it seems like discarding is an effect, which I would take as "Do what you can, so long as the card is not being played for no effect." However, that also seems a bit too good to be true as it means I could play my hand down to just Jessie & James and then force only my opponent to discard two cards. Yet if I read the discarding as a "cost" to use Jessie & James, which means both players would have to have at least two cards they could discard for the Supporter's effect, the that means this card doesn't really have an effect, just a cost to play.

Yes, I am probably making this more complicated than it needs to be. Sorry. >_<