FundsNetwork has urged the regulator to review the "EasyJet" style charging structure of wraps in its consultation on platform charging models.
The decision, marking a U-turn in stance from November's consultation paper, again appeared to sound the death-knell for the bundled pricing model.
But Fidelity has told the FSA the review into bundled pricing will have to look at other sectors of the market - including "ancillary" charges on wrap platforms - in order to carry any credibility.
"In the review the FSA will have to consider other parts of the market and look at how wrap platforms work and how they charge," said Ed Dymott, head of commercial at Fidelity International (pictured).
Dymott compared the charging structures of some wraps to budget airlines.
"EasyJet looks very cheap until you put on all the hidden costs on top," he said. "There are some wrap platforms out there who add a lot of ancillary charges for things such as trading costs, off-line reporting, processing and duplicate statement costs."
Dymott said platforms offering products to consumers through bundled models tend to be more cost-effective than the average wrap.
He added if the consultation into platform charging is to have real weight it must also consider the broader market beyond platforms, looking at the charging structures of life insurers - which also give rebates - and fund managers.
"To view the platform market as entirely different from other parts such as life insurers would be anti-competitive and would likely create market distortion if it was not addressed at the same time."
He added the platform market is not very distinct in the eyes of consumers, with investors buying products from life insurers, wrap platforms and fund supermarkets in much the same way.
"Consumers without doubt view platforms and the medium to long term savings market as a relatively homogeneous market."
Meanwhile, FundsNetwork is just months away from rolling out its unbundled charging structure. Dymott said the model is being developed in response to consumer demand.
"The customers of platforms should determine the most appropriate charging mechanisms, not necessarily the regulator."
Patience must be a watchword
'Misleading, unclear, unfair' promotions
Will extend to wider models
1,414 in 2017/18
UK Multi Cap Income sees success