Trying to set different text for registered and guest customers order confirmation email (using single template, not sure why Magento has two different settings for this?) I've come across that {{if order.getCustomerIsGuest()}}
always evaluates to true rendering {{else}}
useless
I worked it around by using {{if order.getCustomerGroupId()}}
but hoping someone can shed some light what can be culprit of this and to avoid other's pitfalls trying to implement this logic the same way as I originally did