Help with Custom Profile Fields

[GlitchPC]

After a search, I'm still not sure if this has been covered but will ask anyway.

I want to use a Large Text Custom Profile Field....enter text and display it with title.  A user will input text, BBCode allowed and I will use a link so when it is hovered on it displays a member's PC Specs they entered in the input field.  I know I can use "Show enclosed within text" to get this to work but, it will not allow me to use in topic view.  The box is greyed out because of the type of field "Large Text".  If I select "Text Field" it can be checked...but I need miltiple lines.

Can anyone help?

[GlitchPC]

Well then...

Can anyone tell me why you can't use a Large Text box for topic view?