Dry cider's been in secondary for 3 months... do I need to re-pitch before bottling?

I'm following this recipe: https://www.homebrewtalk.com/f81/grahams-english-cider-107152/

But I was talking to a guy at the homebrew store, and he said that all my yeast might be dead by now and I might have to re-pitch. But won't that make it gross and defeat the purpose of letting it clarify for so long?

yeast don't die with time they go dormant. I had started a wine making project with my brother. We had access to tons of fresh fruit and had started over 50 gallons all in 1 gallon batches. this was about 10 years ago. well life happened and one day added to the next and before we new it 10 years had passed, and there the wine sat still in 1 gallon jugs. when I bottled my 10 year old wine I never thought to check the SG because I figured after 10 years the yeast was either dead or or it had fermented out all the sugar. low and behold one of the original gallons had stick probably 9.5 years ago and bottling it was just what I needed to restart the fermentation process. so I learned yeast knows no time limit. After doing some research I found yeast can lie dormant for 1000s of years. tough little bugger to kill.

I have to agree with Daze - yeast are quite resiliant little fungi. A few months without food is nothing is nothing to a yeast colony. I've even had some wine yeast obstinately survive my attempts to kill them.

Personally, unless you gave the guy at your homebrew store a reason to believe that you had extensively tried to erradicate the yeast (i.e. cold crashing, sulphie+sorbate, Sterile filtration, etc.) I would have to question his advice on things in the future.