How is the word 'reason' different from other verbs like it?
Some common synonyms of reason are cogitate, deliberate, reflect, speculate, and think. While all these words mean "to use one's powers of conception, judgment, or inference," reason stresses consecutive logical thinking.
// able to reason brilliantly in debate
Where would 'deliberate' be a reasonable alternative to 'reason'?
The synonyms deliberate and reason are sometimes interchangeable, but deliberate suggests slow or careful reasoning before forming an opinion or reaching a conclusion or decision.
// the jury deliberated for five hours
When is 'reflect' a more appropriate choice than 'reason'?
The words reflect and reason can be used in similar contexts, but reflect suggests unhurried consideration of something recalled to the mind.
// reflecting on fifty years of married life
Writing my dissertation here in the UK and can’t seem to find any other ways of saying the above. Any help is welcome, thank you for your time.
From Wikipedia:
A proximate cause is an event which is closest to, or immediately responsible for causing, some observed result. This exists in contrast to a higher-level ultimate cause (or distal cause) which is usually thought of as the "real" reason something occurred.
If the reason offered is a plausible fake, with bad intent, then you're talking about a pretext.
pretext: a purpose or motive alleged or an appearance assumed in order to cloak the real intention or state of affairs
https://www.merriam-webster.com/dictionary/pretext
If, as the example in your post implies, the reason given is just simpler or easier to understand, then I think you probably can't outdo superficial reason as describing exactly what you're talking about.
There is also putative reason, but a putative reason is a pretext.