hi Si,
you can write your own!  it would be really easy to write a class
derived from the TabControl.  all you would have to do is add one new
property called InitialiseAllTabPages or something like that, and then
invoke the code i gave to the top.  then you can use your own
TabControl instead of the System.Windows.Forms one.  i do this sort of
thing a lot, because i think the listbox and treeview controls are also
lacking some very basic functionality.

if you're interested, see this code below, which is what i have
described above. since the TabControl itself doesn't have a Load event,
i chose the Layout event which happens when the control is first laid
out.  i then remove the event to prevent it from happening again in
case the form resizes.

using System;
using System.Collections;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Windows.Forms;

namespace MyUserControls
{
    /// <summary>
    /// A tab control that allows all the tabs to be loaded when the
tabcontrol loads
    /// </summary>
    public class SmartTabControl : System.Windows.Forms.TabControl
    {
        private System.ComponentModel.Container components = null;
        private bool autoLoadTabPages = false;

        public SmartTabControl()
        {
            InitializeComponent();
        }

        [Category("Custom Options")]
        [Description("Load all tab pages when the tab control loads")]
        [DefaultValue(false)]
        public bool AutoLoadTabPages
        {
            get { return this.autoLoadTabPages; }
            set { this.autoLoadTabPages = value; }
        }

        protected override void Dispose( bool disposing )
        {
            if( disposing )
            {
                if(components != null)
                {
                    components.Dispose();
                }
            }
            base.Dispose( disposing );
        }

        #region Component Designer generated code
        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            //
            // SmartTabControl
            //
            this.Layout += new
System.Windows.Forms.LayoutEventHandler(this.SmartTabControl_Layout);

        }
        #endregion

        private void SmartTabControl_Layout(object sender,
System.Windows.Forms.LayoutEventArgs e)
        {
            if(this.autoLoadTabPages)
            {
                // store the originally selected tab to set the state of the
control back to it's original state
                int originallySelectedTabIndex = this.SelectedIndex;

                // iterate through each TagPage in the collection and select it
                foreach(TabPage tab in this.TabPages)
                    this.SelectedTab = tab;

                // detach the Layout event because we only want it to happen once
(could happen later if the form is resized or controls changed etc.
                this.Layout -= new LayoutEventHandler(SmartTabControl_Layout);

                // restore the selected tabindex
                this.SelectedIndex = originallySelectedTabIndex;                
            }
        }
    }
}