After all, the A-share market is trading at very high valuations. It is also natural for companies to seek listings where their customers are, for the sake of brand building and price stability.

To understand their reservations, I refer you to a recent comment by Wang Xiaochu, chairman of China Telecom. 'There is no reason to issue A shares. It will be our last option ... bond financing offers us far more flexibility,' said Mr Wang who is known as a maverick - in response to a media query.

Indeed, why should a company issue A shares when its balance sheet is decent enough to tap the screamingly cheap debt market? Chapter one of any book on financing says the equity route is generally more expensive than the debt.

Yes, a sky-high valuation undercuts this rule and the A-share index has been trading up in the clouds. But as previous public offerings show, Hong Kong-listed companies heading north are not getting the money from the high valuations.

Instead, their offerings are always priced at a 3 to 5 per cent discount to the H shares, after 'consultation' with the CSRC. Much of the fat in the aftermarket is soaked up by powerful corporates and insurers getting a big chunk of the new shares.

This cost concern is more egregious when a company is cash rich, as is the case for most of the targeted firms. A-share issues will only add more pressure on their return on equity.

One way out from this is to have the controlling shareholders, in this case the state, sell shares in the mainland listing - that way, the money goes to the parent, and other shareholders do not see a dilution in their holdings. On the surface, this option will leave the listed entity unharmed.

China Mobile, which is too big in size, profit and name to defy government orders, has chosen this route. The management is clear on its preference.

This raises the more controversial issue of a state sell-down, a taboo in the mainland stock market. What the regulator does not want to do is have the homecoming of red chips being perceived as the government cashing out. There is also the question of how state shares should be priced.

Still, even if the government agreed to a state sell-down, the listed entities would have the intangible costs to consider.

The most significant one is regulatory. A Shanghai listing would put companies under the control of CSRC, which has a different set of rules and goals than its Hong Kong counterpart.

The management of the key state-owned enterprises know too well how costly this can be. For Hong Kong-registered red chips, which have been enjoying the freedom of the city's laws, the loss of flexibility would be more damaging than to other mainland companies. How significant the loss is will depend on how much the Hong Kong regulator has given in to its mainland counterpart.

A second concern is the strategic cost - listing in an immature market like the mainland's, where valuations dwarf international levels, comes with potential hazards.

The management of China Eastern Airline understands this dearly. Bleeding red for consecutive years, the airline has been talking to Singapore Airlines about a stake sale for months in return for financial and managerial resources.

But China Eastern's A shares have been trading at a significant premium to its shares in Hong Kong. The problem now is how to strike a price that is acceptable to both the international buyer and mainland shareholders.

As China's corporations enter the era of mergers and acquisitions, this is the type of cost that no responsible management can ignore. It's a matter of weighing that cost against the benefit of having the A-share platform to make it easier to do domestic acquisitions.

No wonder some managements are saying no to the homecoming order. However, it will only be a matter of time before they have to submit.

As China continues to be flooded with liquidity, monetary and administrative measures will do little to cool the red-hot stock market. The regulator is relying on the listings of these key corporations to do the magic for them and mop up some liquidity.

Their HK$200 billion in profit will lower the overall valuation average. Their inclusion into the benchmark index will provide the kind of diversity and stability that will make prudent the offering of index futures, which in turn will allow shorting, and it is hoped, a change from the current profit-by-buy-only scenario in the mainland.

We can only hope that corporate management can bargain for something sweet for their shareholders in return for their sacrifice.

It won't be long before we hear the results.