The tender offer is $4, If they don't get enough shareholders offering their shares SVU can issue more shares at $4 to Cerberus.
As for is the tender offer a good deal, that depends on what you bought your shares for. I got in around $2.50 less than 2 weeks ago, so I sold some shares at $3.50 for a great profit. But I do believe the stock is going to go up well over $4 eventually so I am holding a lot of shares still. I see SVU got rid of a lot of debt with the sale off to Cerberus and the base remaining wholesale business they have is what they were doing so well with before they bought the Albertsons.
No the tender offer was determined based on offering a premium over the average selling price for a determined period prior to the tender offer. Trading up or down after the tender will only influence the decision to accept the tender or not.
You are a true long. I know that you have been here for years talking/asking about SVU. Do you mind sharing your position (cost basis) and interest in Supervalu? Are you an employee?