New grad vs senior dev
from
ericlippert.com
[...] any solution that involves allocating a table, preprocessing strings, and so on, is going to take longer to do all that stuff than the blazingly-fast-99.9999%-of-the-time brute force algorithm takes to just give you the answer. The additional complexity is simply not worth it in scenarios that are relevant to VB developers.
(emphasis mine)
Being a senior developer is not just about applying patterns everywhere, but also knowing when not to. It's about finding the right solution for the right problem and discarding unnecessary things (patterns/complexity, etc.), because You Ain't Gonna Need It.