This is a continuation of
https://github.com/polkadot-fellows/xcm-format/pull/55 following the
migration of XCM RFCs to this repo.
# Summary
Remove the `require_weight_at_most: Weight` parameter of the Transact
instruction.
# Motivation
The UX of using Transact is not great, and one part of the problem is
guesstimating this require_weight_at_most.
We've seen multiple Transacts on-chain failures caused by the
"incorrect" use or the parameter. In practice, this parameter only adds
UX overhead. Use cases fall in one of two categories:
1. Unpaid execution of Transacts - in these cases the
require_weight_at_most is not really useful, caller doesn't have to pay
for it, and on the call site it either fits the block or not;
2. Paid execution of single Transact - the weight to be spent by the
Transact is already covered by the BuyExecution weight limit parameter.
We've had multiple OpenGov root/whitelisted_caller proposals initiated
by core-devs, completely or partially fail because of incorrect
configuration of `require_weight_at_most` parameter. This is a strong
indication that the instruction in its current form is hard to use.
---------
Signed-off-by: Adrian Catangiu <adrian@parity.io>
Adrian Catangiu