Anyway, if you really want a closing brace to flash its opening mate, a slightly ugly hack is to make a shortcut to type “}” followed by a left-arrow and a right-arrow. A Textmate macro won't quite work, presumably since you’re not actually pressing the right-arrow key, but you can program the amazing Karabiner (
https://pqrs.org/osx/karabiner) to do it by adding this to its private.xml:
<item>
<name>Textmate Brace Closer</name>
<appendix>Turn "}" into }←→ to flash the opening brace</appendix>
<identifier>private.bracer</identifier>
<appdef>
<appname>TEXTMATE</appname><equal>com.macromates.TextMate.preview</equal>
</appdef>
<only>TEXTMATE</only>
<autogen>--KeyToKey-- KeyCode::BRACKET_RIGHT, MODIFIERFLAG_EITHER_LEFT_OR_RIGHT_SHIFT, KeyCode::BRACKET_RIGHT, ModifierFlag::SHIFT_L, KeyCode::CURSOR_LEFT, KeyCode::CURSOR_RIGHT</autogen>
</item>