Tata steel questions

People might have heard of events happening around Tata steel camp.

Promoter’s holding company Tata sons has decided to increase its stake in Tata steel through preferential allotment and warrants route. Though we understand it is intended to shun any potential hostile bid by steel baron Mittal, what I fail to understand are……

1. If injecting further money into the business was the motive, why can’t they go with all out preferential issue rather than some amount of warrants?
2. I hope warrants are another form of options (like ESOP for executives) where in promoter does not need to shell out money immediately, but with a premium (like a call or put option) at the time of Warrant issue. Given these assumptions being true, what would probably be the exercise price as pronounced by ‘SEBI prescribed price formula’?
3. This question is not directly related to Tata steel, but with games played around convertible warrants. Does any one have a clue on what the price determination formula that SEBI prescribes for an unlisted company is? Has anyone closely followed DLF case where minority shareholder was apparently betrayed by the greedy promoter? Are there any similarities between DLF and Tata steel warrants? If the real motive is to raise money, why can’t Mr.Ratan Tata provide warrants for every Tata steel shareholder instead of Tata sons?

The news item (from Hindu business line) is below for reference.
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Separately, Tata Steel informed the BSE that it would issue on preferential basis 2.70 crore ordinary shares of Rs 10 each at a price of Rs 516 per share for Rs 1,393.2 crore to Tata Sons.
Also proposed were 2.85 crore warrants, each entitling Tata Sons to subscribe to one ordinary share of Tata Steel against cash payment. The promoter company would pay Rs 51.60 per warrant on allotment; Tata Sons can exercise its option after April 1, 2007but not later than 18 months from the date of issue, in accordance with SEBI prescribed pricing formula.
"You may ask why this injection of funds (Rs 6,500 crore ) is not being made as a rights issue to shareholders. The main reason for that is - through an overseas issue we can perhaps obtain prices that are close to market prices today, which, we would not be able to do in the case of shareholders who would justifiably want a discount, and a substantial discount from market value. This we will consider in time as we always have. But if we want to hold dilution to a minimum and protect existing shareholders, we expect to raise these funds in a manner that it will not exceed 15 per cent of the prevailing paid-up capital of the company.