As ever with financial markets, what matters is the difference from expectations. Investors did not think the G20 summit would produce an easing of trade tensions between the US and China, therefore stock markets surged after Donald Trump declared that relations had taken “a BIG leap forward”.

Yet it is only sensible to believe Trump’s hyperbole when there is something on the table to inspect. All that has been agreed so far is a pledge to keep talking until March. The tariff increases the US had planned for January won’t go ahead, which is clearly positive for markets, but it requires extreme optimism to believe a three-month truce can produce a negotiated deal on all the areas in the Trump administration’s sights.

Only one aspect could be considered vaguely straightforward. It is clearly within Beijing’s gift for China to buy more goods from the US to address the trade imbalance between the two countries, which is where this dispute started. But a mutually acceptable definition of “substantial” is anybody’s guess at this stage. For China to restart imports of US soybeans doesn’t move the dial on its own.

The biggest hurdles, though, are intellectual property and access to Chinese markets for US companies. Beijing, for official purposes, wants to open up its economy but the pace of change tends to be glacial. Trump may be contemplating something close to a complete rewiring of the Chinese economy. For a Beijing regime stuck with debt-laden state-owned enterprises, a full blast of foreign competition will be a terrifying prospect.

Maybe, for all the obvious difficulties, there is still a deal to be struck by March. But it’s probably not the way to bet. The deadline is too tight. The trade ceasefire looks fragile.

GSK’s £4bn punt on biotech pipeline is chunky but expected

On Monday morning, GlaxoSmithKline’s shareholders applauded the sale of Horlicks, plus a few add-on products, to Unilever for £3.1bn. In the afternoon, they experienced a bout of nerves as the chief executive, Emma Walmsley, spent the proceeds before they had arrived by agreeing to pay £4bn for Tesaro, a US biotechnology firm with a promising drug for ovarian cancer. GSK’s shares fell 7%.

The reaction is, perhaps, understandable. A £4bn punt on a biotech pipeline is chunky even for GSK, as demonstrated by the short-term effect on earnings: they’ll be diluted by “mid to high single digit percentages” for two years and the longer-term benefits, assuming they arrive, won’t be felt until 2022. By contrast, the Horlicks collection offered the warm glow of predictable cashflows.

GSK shareholders cannot, however, grumble about Walmsley’s switch. She’s been saying for ages that her top priority is to boost the underpowered but core pharmaceutical division. That was the point of hiring Hal Barron, a big name in the US, as chief scientific officer and giving him licence to make a few bets.

The takeover premium on the Tesaro deal – 110% – looks enormous but biotech is that kind of industry: big pharma has to swallow hard and pay up to back its scientific analyses. On this occasion, GSK shareholders can at least take comfort that Luke Miels, another Walmsley recruit, came from AstraZeneca, which makes Lynparza, the main competitor in ovarian cancer to Zejula, Tesaro’s leading product. Miels, in other words, ought to be ideally placed to judge whether Zejula is a future blockbuster.

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An open question, though, is how many more big biotech bets Walmsley has in mind. She’s not saying, but may be well advised to prepare the ground if many more £4bn-ish outlays are required to reinvigorate the drugs pipeline. The only certainty at GSK is that shareholders love their dividend. They will not want it to be endangered by many more short-term hits to earnings.

Mike Ashley’s high-street idea exposes politicians’ lip service

“It is the internet that is killing the high street,” declared Mike Ashley. It’s hard to argue with that, nor the Sports Direct founder’s remark that landlords “have to take their share of the pain”, which is already happening.

Ashley’s provocative suggestion was that retailers with more than 20% of sales online should pay a 20% tax on those sales. That’s not going to happen: no government is going to upset online shoppers by re-tilting the economics of retailing to that degree. Ashley was talking his book.

But if his real point was that ministers have paid lip service to the cause of “saving the high street”, and engaged in a series of ineffectual tweaks and minor reliefs, he’d be right. Politicians blow a lot of hot air about the high street, which was a point worth making.