Discrepancy in CSS gradient property in twentyeleven

Hi

I have searched the forum but cannot find a thread that address my issue. I am not an advanced WP coder hence if I am repeating something which is covered before I do beg your pardon.

In the twentyeleven theme I can see that the gradient property is not consistently defined for all browsers. Look at the two exaples from the styles.css file.

.featured-post .feature-text:after,
.featured-post .feature-image.small:after {
	content: ' ';
	background: -moz-linear-gradient(top, rgba(255,255,255,0) 0%, rgba(255,255,255,1) 100%); /* FF3.6+ */
	background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,rgba(255,255,255,0)), color-stop(100%,rgba(255,255,255,1))); /* Chrome,Safari4+ */
	background: -webkit-linear-gradient(top, rgba(255,255,255,0) 0%,rgba(255,255,255,1) 100%); /* Chrome10+,Safari5.1+ */
	background: -o-linear-gradient(top, rgba(255,255,255,0) 0%,rgba(255,255,255,1) 100%); /* Opera11.10+ */
	background: -ms-linear-gradient(top, rgba(255,255,255,0) 0%,rgba(255,255,255,1) 100%); /* IE10+ */
	filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#00ffffff', endColorstr='#ffffff',GradientType=0 ); /* IE6-9 */
	background: linear-gradient(top, rgba(255,255,255,0) 0%,rgba(255,255,255,1) 100%); /* W3C */
	width: 100%;
	height: 45px;
	position: absolute;
	top: 230px;
}

#access {
	background: #222; /* Show a solid color for older browsers */
	background: -moz-linear-gradient(#252525, #0a0a0a);
	background: -o-linear-gradient(#252525, #0a0a0a);
	background: -webkit-gradient(linear, 0% 0%, 0% 100%, from(#252525), to(#0a0a0a)); /* older webkit syntax */
	background: -webkit-linear-gradient(#252525, #0a0a0a);
	-webkit-box-shadow: rgba(0, 0, 0, 0.4) 0px 1px 2px;
	-moz-box-shadow: rgba(0, 0, 0, 0.4) 0px 1px 2px;
	box-shadow: rgba(0, 0, 0, 0.4) 0px 1px 2px;
	clear: both;
	display: block;
	float: left;
	margin: 0 auto 6px;
	width: 100%;
}

featured-* properties includes the IE specific properties, whereas #access does not. Is there a reason for that, or is that an omission?

Many thanks

Riz