Can Reaction cards be used in response to playing a card that doesn't have a 'when you play me' effect?

Ruling: When you play/gear a unit, a chain is still formed, but as a permanent it instantly resolves without giving priority to either player, so you cannot react to it being played on the board.

Sequence:

• A card is played/geared
• A chain is formed
• The permanent instantly resolves without priority being given
• No opportunity to use Reaction cards

Nuances:

• This applies specifically to permanents (units)
• The chain exists but resolves immediately without allowing reactions