Lines 368-372 from effects.js 1.4a2

368: for ( var i in this.options.curAnim ) {
369:     if ( this.options.curAnim[i] !== true ) {
370:         done = false;
371:     }
372: }

it is unnecessary to continue the for loop once we reach line 370. Depending on the number of properties which have to be animated (default 11) this would saves a few cycles for every animated element.

Proposed "speed" batch

370a371
>         break;

Resulting code

368: for ( var i in this.options.curAnim ) {
369:     if ( this.options.curAnim[i] !== true ) {
370:         done = false;
371:         break;
372:     }
373: }