Not sure I agree with this. I will frequently do things like:
```ruby 
 if object.save
```
or
```ruby 
 if object.update_attributes(params)
```
I think this pattern helps reduce unnecessary control flow nesting.

To use your example, if after a successful payment i want to ```print_receipt```
the example goes from
``` ruby
print_receipt if payment_due? && process payment!
```
to 

```ruby 
if payment_due?
 payment_successful = process payment!
 if payment_successful
   print_receipt
 end
end
```

Granted print_receipt would probably be part of process_payment but hopefully you can see what im getting at