Transfers seem much faster than Invokes of `nil`

[mikera]

Discovered in cloud testing.

For some reason Transfer type transactions execute much faster than an Invoke of nil.

Main difference appears to be more Blocks getting processed in e.g. 240 vs 60 blocks per second with 100 concurrent users. Block sizes are a similar order of magnitude.

[mikera]

It is possible that the *lang* capabilities result in extra overhead when doing an invoke of nil, but surprising that it makes this much difference. Added this comment as a reminder to check this path.