Proposed New Transition Mixin Set for http://github.com/hzdg/bedrock/

transition.css

.verbose {
  -webkit-transition-property: -webkit-transform;
  -moz-transition-property: -moz-transform;
  -ms-transition-property: -ms-transform;
  -o-transition-property: -o-transform;
  transition-property: transform;
  -webkit-transition-property: 1s;
  -moz-transition-property: 1s;
  -ms-transition-property: 1s;
  -o-transition-property: 1s;
  transition-property: 1s;
  -webkit-transition-timing-function: ease-in-out;
  -moz-transition-timing-function: ease-in-out;
  -ms-transition-timing-function: ease-in-out;
  -o-transition-timing-function: ease-in-out;
  transition-timing-function: ease-in-out;
  -webkit-transition-timing-function: 0.1s;
  -moz-transition-timing-function: 0.1s;
  -ms-transition-timing-function: 0.1s;
  -o-transition-timing-function: 0.1s;
  transition-timing-function: 0.1s;
}
.shorthand {
  -webkit-transition: opacity 0.3s;
  -moz-transition: opacity 0.3s;
  -ms-transition: opacity 0.3s;
  -o-transition: opacity 0.3s;
  transition: opacity 0.3s;
}
.inline-prefix-limit {
  -webkit-transition-property: -webkit-opacity, height;
  -moz-transition-property: -moz-opacity, height;
  -ms-transition-property: -ms-opacity, height;
  -o-transition-property: -o-opacity, height;
  transition-property: opacity, height;
}

transition.less

// MIXINS
.transition(@transition) {
	-webkit-transition: @transition;
	-moz-transition: @transition;
	-ms-transition: @transition;
	-o-transition: @transition;
	transition: @transition;
}

.transition-property(@property) {
		-webkit-transition-property: @property;
		-moz-transition-property: @property;
		-ms-transition-property: @property;
		-o-transition-property: @property;
		transition-property: @property;
}
  
.transition-property(@property, @prefix) when (@prefix = true) {
    -webkit-transition-property: ~"-webkit-@{property}";
		-moz-transition-property: ~"-moz-@{property}";
		-ms-transition-property: ~"-ms-@{property}";
		-o-transition-property: ~"-o-@{property}";
		transition-property: @property;
}
  
.transition-duration(@duration) {
		-webkit-transition-property: @duration;
		-moz-transition-property: @duration;
		-ms-transition-property: @duration;
		-o-transition-property: @duration;
		transition-property: @duration;
}
  
.transition-timing(@timing) {
		-webkit-transition-timing-function: @timing;
		-moz-transition-timing-function: @timing;
		-ms-transition-timing-function: @timing;
		-o-transition-timing-function: @timing;
		transition-timing-function: @timing;
}
  
.transition-delay(@delay) {
		-webkit-transition-delay: @delay;
		-moz-transition-delay: @delay;
		-ms-transition-delay: @delay;
		-o-transition-delay: @delay;
		transition-delay: @delay;
}

// Keeps this from being a breaking change to bedrock,
// which already has a .delay() mixin
.delay(@delay) { .transition-delay(@delay) }

// USAGE
.verbose {
  .transition-property(transform, true);
  .transition-duration(1s);
  .transition-timing(ease-in-out);
  .transition-delay(0.1s);
}

.shorthand {
  .transition(opacity 0.3s);
}

.inline-prefix-limit {
  .transition-property(~"opacity, height", true)
}