Serendipity, your question about the sale affecting the share price depends on how the gain is realized for shareholders and how much TXN will receive for Eagle Ford.
On the 1st point: If TXN keeps the cash and shareholders receive, say, a token special dividend, etc. then no, the price would not rise enough. As you imply, company assets (even cash!) are highly discounted these days. But if shareholders get the proceeds as a payout through a special dividend and return of capital, the share price would rise just below the value of the future payout. The certainty of shareholders receiving the asset as cash tremendously reduces the discount effect. (same effect as recent DMG situation and with most takeover offers).
On the 2nd point: A $200M EF sale would not be enough. Mgt either needs a much higher sale price (above $260M -- $37k/acre) or sale of additional assets or the entire company. Then enough of the proceeds are returned directly to shareholders so the share price reliably jumps above $1.05.
The question is whether such a sale will take place and at what price. Sorry, my crystal ball just went hazy.
TXN Price at posting:
47.5¢ Sentiment: Buy Disclosure: Held