Accesskey are a disputed accessibility tecnique see for example this article *and discussion* http://juicystudio.com/article/firefox2-accesskeys.php

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• Using the access key on a required simple field causes the correspondent input control to be focused. For example use [F] to focus on the [First Name] text input.
• Using the access key on a optional simple field that currently has no value causes the correspondent input control to be displayed and focused, using the access key on an optional field that currently has a value has the same behavior of a required field: causes the input to be focused. For example use [D] of [Date Of Birth] to create and focus on the date input.
• Using the access key on a complex field causes the input of the first of its fields to be focused. For example use [A] of [Address] to focus on the [Full Street Address] input. Is still possible to use the access key of the first field of the complex type bbut here is not defined, it is defined instead for [Friend].
• When a field is optional and hidden like [Friend] and [Date Of Birth] in this example, is possible to use the access key in order to create a value and show a control for typing data in. Once an optional field has its control displayed, the focus act in the same way of a not optional field, so in the example, the [Friend] label focuses on the [First Name] input control and [Date Of Birth] on its input control.
• On some browsers is possible to iterate through fields that have the same access key pressing it multiple times. In this example using [F] we can iterate through the [First Name] fields, when [Friend] has a value.