I make no apology for describing a row over PG Tips tea bags getting fractionally smaller as a storm in a teacup. (Clichés may be like a red rag to a bull for some writers, but not me.)

The Daily Mail this weekend devoted the best part of half a page to a story headlined ‘Now PG Tips puts less tea in its tea bags’, in which it describes a change “made so quietly that it seems even some supermarkets were caught by surprise”.

Readers were told a 250g pack of 80 bags had dropped to 232g - with no corresponding change in price – and that other PG Tips packs had also shrunk. But, to my mind, the key point is that the number of bags per pack has not altered. An 80-bag pack is still an 80-bag pack.

What PG Tips owner Unilever claims to have done is develop new tea bag paper and a “new blend that delivers all the same great fresh PG tips taste while reducing the content of each tea bag by 0.2g”. 

If so - and if a drinker genuinely won’t notice the difference between the old tea bag and the new version - then consumers are no worse off.

And this may well be the case, as one tea industry expert – with no connection to PG Tips - told me different teas brew at different rates and produce different taste qualities, so the amount of tea may not impact the drinking experience.

The Mail story makes the comparison between the PG Tips case and other uses of the Grocery Shrink Ray (as it dubs it). But this isn’t like reducing the size of a chocolate bar or selling fewer crisps in a crisp bag – two examples in which the final quantity of product a shopper consumes has been reduced. And I don’t recall such complaints when squash manufacturers began switching to double-concentrate formats.

I reckon where PG Tips may have gone wrong is in not being 100% up front with consumers. It has described the change on pack and on the brand website (under the heading of ‘sustainability’), and pitched it as a green initiative to reduce waste. A quick glance at the PG Tips Facebook page this afternoon suggests that won’t cut it with all consumers, with one sarcastically opining: “because we all know that tiny bits of wet plant leaves in landfill are a huge problem”.

And while environmental benefits may well have motivated the change to a degree, consumers aren’t stupid. They understand the cost of ingredients rise and may well have read stories in the national press about how Brits are buying and drinking less everyday tea.

So if there are other reasons for the change then be honest about them. Tell consumers the market is challenging (PG Tips sales fell 3.3% in 2014 according to the Britain’s Biggest Brand supplement in this coming weekend’s The Grocer mag) and, if cost is one of the reasons for the latest move, then tell shoppers you need to make changes or put prices up.

I don’t believe Unilever’s new tea bags are ‘the great tea rip-off’ the Mail describes them as. But all suppliers should bear in mind another cliché whenever engineering pack sizes: honesty is the best policy.