hard winter cycling? anyone who will not benefit

Question for the gurus.  Will everyone benefit from some good hard riding this time of the year after time off?  My wife has been out of training for about 6 months.  Would it benefit her to start with some easy zone 2 riding to get some fitness back or can she start doing some harder intervals right away. 

And I have been slacking/off bike since October, trying to increase my running, and getting back on the bike seemed harder than usual.  Same question for me.  Zone 2 stuff for week or two to get back in action or start going for it with harder intervals?

We both train by HR, and I have used Trainer Road off/on.

Plan on riding 3 days a week, Tu/Th 45min-hour session, and longer ride on Sat, starting to build between 1-1:30 and increase every week.  Still plan on running 4-5 days a week.  Following the Fink competitive plan- or modified version of.  Oly-A race 17 weeks out.  And Beach to Battleship end of october with bunch of sprints sprinkled throughout year.

Thanks.